The TARDIS: It's possibly not the most famous time machine in science fiction (yet) - that would probably be a certain car that you'll meet below - but it's definitely the most distinctive. Doctor Who's stylish acronymtastic (its name stands for Time And Relative Dimensions In Space) mode of transport may have started life as a means of keeping the show's 1963 first episode budget down thought up by BBC staff writer Anthony Coburn, but it's since become one of the most recognizable images in SF TV. Something that the BBC must be happy about, having trademarked the familiar blue box in 2002.

The Cosmic Treadmill: A glorious example of Silver Age comic book (il)logic, the Flash's self-built "cosmic treadmill" allowed him to travel backwards and forwards in time - as well as through parallel universes - by running so fast that he'd hit the perfect vibrational frequency that would allow him to zip away. Created by Flash and Green Lantern writer John Broome, the somewhat ridiculous gimmick has stayed around in the Flash books ever since, proving that some ideas are so dopey that they cross the line into permanently awesome.
Doc Brown's DeLorean: What is it about the time machine from Back To The Future that makes it so perfect? That it was one of the first green time machines (after that whole plutonium thing, of course)? The very specific need for a very particular speed? The fact that it put the already spacey look of one of the '80s most impractical cars to good use? Perhaps all of the above, but what will always single it out for our love and adoration was the fulfillment of Doc Brown's promise that, where we're going, we won't need roads.

The Time Bubble: Ah, the simplicity of 1950s design. The Time Bubble - so named because it's a clear bubble that travels through time - first appeared in 1958's Adventure Comics #247 as the 30th century's favored method of time-travel, and who can deny something with such sleekness and beauty? Thank creators Otto Binder and Al Plastino for what must surely be the objet d'art aesthetic of purity that all other time machines should aspire to.

The Time Tunnel: On the one hand, I should be more worried that they never really got the time tunnel to actually work properly, but on the other, dude. It was a time tunnel, an honest-to-goodness man-made version of the Guardian of Forever, but with less Joan Collins - You didn't need to operate any funky machinery or maintain your internal vibrational frequency, you simply needed to enter the tunnel and off you went. The only drawback, if the experience of Tony Newman and Doug Philips is anything to go by, is that you'll never get to come home again. But if you liked your present-day life so much, why would you time travel in the first place, right?

Step one: Discover Ace, the Proto-Rose.

The last couple of years Doctor Who was on the air in the late 1980s, the writers started experimenting with the often-boring relationship between the Doctor and his cute travel companion. They introduced Ace, a rebellious teenager with a love of explosives. At first, the Ace-Doctor relationship was just a little spicier than the traditional Doctor/ambiguous-friend pairing, but over time it became a lot more. The Doctor started putting Ace through a series of tests and forcing her to confront her fears. She, in turn, started questioning the Doctor's goals and methods more than any companion before her. The Doctor-Ace relationship provided an inspiration for some of the more fully realized companions of today, like Rose.

The final three Ace stories are all on DVD, and they're probably the best way for fans of the RTD era to delve into the new series. (Ignore the horrendous opening credits, the mostly cheese-tastic incidental music and the worse-than-usual special effects.)

In "Ghostlight," the Doctor takes Ace to the haunted house that freaked her out when she was a kid, except they visit it in the Victorian era and she discovers she had good reason to be freaked out. "Ghostlight" is full of weird clever touches and riffs on Victorian naturalism and the absurdity of the British explorer archetype. (And a lot of that stuff ends up being less than meets the eye, sadly.) But at its core, it's about Ace confronting her deepest fears and getting closer to being the Doctor's equal.

And then in "Curse Of Fenric," the Doctor takes Ace to World War II England, where she meets her own mother as a baby and discovers that someone has been manipulating her all along. But "Curse Of Fenric" is mostly the episode steps up and starts being the clever one — there's a fantastic moment halfway through where the Doctor is counting on nobody figuring out the secret of the Viking runes. And he doesn't realize Ace has figured it out ages ago, because he's understimated her intelligence. Finally, in "Survival," Ace returns to her juvenile-delinquent roots and discovers that all her old friends have gotten sucked into a planet that's basically a weird parody of the "survival of the fittest" world the stupid adults in her life were trying to prepare her for all along.

These three stories stand the test of time quite well, and they show Ace growing and developing as a character, whose inner life is just as important as the Doctor's latest scheme. (A fourth Ace story, "Remembrance Of The Daleks," is also on DVD and has some nice moments.) Supposedly if the show hadn't been canceled, we would have learned the reason the Doctor was putting Ace through so much trauma: he was grooming her to become a Time Lord. The following season would have seen Ace enrolling in the Time Lord Academy on Gallifrey. (Her story continued in a different way in a series of novels, but a radio play, "Death Comes To Time," did show her going through a sort of Time Lord training.)

Step two: Sample the Baker era.

And yes, by "Baker era," I do mean "Tom Baker." I would never advocate anybody putting themselves through the torment of watching any of Colin Baker's mid-1980s tenure as the Doctor. Tom Baker played the Doctor from 1974 to 1981, and his manic (and sometimes menacing) portrayal was huge in England and won over American audiences. His portrayal degenerated into schtick after a few years, but at first he was the edgiest, funniest and most unpredictable of the Doctors.

I was surprised when I interviewed Julie Gardner, executive producer of the new Who, and she mentioned that showrunner Russell T. Davies had given her a list of classic Who episodes to watch before they relaunched the show. The list was all Tom Baker, instead of the later stories I'd been expecting: "Pyramids Of Mars," "Talons Of Weng-Chiang" and "City Of Death." (I wouldn't recommend "Talons Of Weng Chiang," though: the racial stereotyping is actually painful to watch.)

The best Tom Baker stories remain fresh because they're all about improvisation. Tom Baker is constantly improvising his performance, keeping the other actors on their toes. And his Doctor is written as the most improvisational as well. He's constantly being backed into a corner and bluffing his way out, making plans that fall flat and then making up new plans on the spot, and building gadgets out of scrap. And it's really in the Baker era that the show's scripts become so multi-layered that any child watching will probably miss half of what's going on. (And still love it.) Here are the Tom Baker episodes that actually hold up, weak special effects and all:

• "Ark In Space." Just remember that bubble wrap wasn't as common back then, and it actually looked sort of cool at the time. And "Ark" is a classic for a reason: the Doctor is out of his depth from the moment he's trapped in an airless room with the life-support turned off to the moment he's facing an army of spacewalking giant bugs, with no way to stop them. Classic Who moment: the Doctor makes a macabre observation, followed by "I'm afraid." His companion Sarah Jane tells him to stop making jokes, and he responds: "When I say I'm afraid, I'm not making jokes."
• "Pyramids Of Mars." Another one where the Doctor is outclassed and overpowered from start to finish, and he keeps making clever plans that fail horribly. The interplay between Sarah Jane and the Doctor is never better than in this episode — partly because the story's female director took some of the Doctor's dialog and gave it to Sarah Jane. So instead of the Doctor explaining everything to Sarah Jane, she's figuring stuff out on her own.
• "Robots Of Death." Here's a clever twist: robots go around killing people, not by shooting them with lasers or firing nanites at them — but by strangling them to death with their powerful robot hands. It's a surprisingly gruesome story, by Blake's 7 writer Chris Boucher, and it explores some serious questions about humans' dependence on technology. The society in "Robots" can't function without robotic assistance, but the humans are secretly (or not so secretly) terrified of robots. So what happens when a whole gaggle of robots go berzerk and kill everybody? "I should think it's the end of this civilization," the Doctor says far too casually. "Robots" also features Leela, the knife-wielding jungle woman who traveled with the Doctor for a couple of years, and whose first response to any situation is lethal force.
• "City Of Death." I'm hesitant to recommend this one, because it's pretty slow going at first — the Who team managed to film in Paris, and celebrated with lots and lots and lots of shots of the Doctor running around the city. But once it gets going, the script mostly written by Douglas Adams is pretty much irresistibly glib and clever. Not to mention a cameo by Monty Python's John Cleese in his prime.

Step three: Check out some other classics.

I'm pretty confident that if you've followed steps one and two, you should already be a fan of the classic series. At that point, you should be open to sampling a lot of the other stories from the show. Here are a couple of ground rules:

1) Don't watch any story over four episodes long. (Or about 90 minutes.) While there are a few notable exceptions, by and large the longer a Who story gets, the more it gets padded out for length. Even some four-episode stories tend to have a third episode where the Doctor is locked up for twenty minutes or gets captured and escapes a couple of times. The show's producers frequently dragged out stories for longer than they deserved, in order to save money on sets and costumes. A few possible exceptions: "Dalek Invasion Of Earth," "Doctor Who And The Silurians" and "Inferno."

2) Stay away from the black and white 1960s stories until you're well and truly indoctrinated. There are some definite gems remaining from the 60s, including the aforementioned Dalek invasion story and "Tomb Of The Cybermen," but the first two Doctors' adventures haven't aged as well, by and large, as the rest of the show. Not just because of the old-movie look of the black and white, but also because they were filming literally an episode per week, with a couple of sets, and most of the episodes have a very stagey quality to them. They're basically stage plays on film.

3) Try to take breaks between episodes. I should have mentioned this earlier. When I lived in England as a kid, we would have a week between 25-minute episodes, and those silly cliffhangers would feel all-consuming. A lot of stories feel stretched out and slow if you watch them all in one sitting, but they feel urgent and super-fast if you watch them an episode at a time. Although the Tom Baker stories were frequently shown in "movie" format in the U.S., with all the episode breaks edited out, and they seemed to hold up fine. (I remember watching a 7-part Jon Pertwee story in "movie" format, and I nearly clawed my face off.)

That said, here are a few other stories that are on DVD that are especially worth checking out for people who are new to the classic series:

• "Claws Of Axos." For now, at least, it's the only classic story featuring the original version of the Doctor's arch-enemy the Master that's out on DVD and isn't 6 episodes long. It's got some extremely silly/cheesy moments, especially pompous civil servant Mr. Chinn, but it's also got some fun action sequences with U.N.I.T. and a somewhat clever story about gullible humans being lured to their doom through their own greed.
• "Curse Of Peladon." Not out on DVD, but hopefully it will be at some point. It's a fun romp about the Doctor visiting a mock-medieval planet that's trying to join a galactic Federation. The aliens are goofy and fun, and it's the only story with the Ice Warriors that isn't overly long and/or in black-and-white.
• "Carnival Of Monsters." Another silly romp, written by supreme Who screenwriter Robert Holmes. It drags a bit in places, due to a time loop that makes some of the characters act out the same scene over and over. But it's also got one of Holmes' classic huckster characters: a carnival con-man, who's got a machine full of captured alien races (including humans) living out a moment in time over and over. The carnival attraction ends up causing a revolution on an alien planet.
• "The Time Warrior." It introduces Sarah Jane and the cloned warrior Sontarans. It's also one of the wittiest scripts from Holmes, having fun with rogues and ruffians in medieval England.
• "Genesis Of The Daleks." Almost mentioned this in the "Tom Baker" section above. If you're up for a six-part story, this one is pretty great. The only good story featuring Davros, the creator of the war-cyborg Daleks. It's famous for having the gritty opening showing people being machine-gunned in slow motion, but it also has a lot of other great moments, with the occasional slow bit.
• "The Keeper Of Traken," "Logopolis" and "Castrovalva." The return of the Master, and the regeneration of Tom Baker into Peter Davison. These stories are fun to watch, and you can't help wishing that some of the touches of character development in the companions had been followed up on instead of ignored. The new Master starts out wonderful, but manages to fall apart by the end of "Castrovalva," sadly.
• "The Visitation." Another historical story, featuring an alien who wants to supercharge the Black Plague and wipe out humanity. Peter Davison is still finding his feet as the Doctor in this story, but he gives one of his most fiery performances.
• "Earthshock." The story that brought back the Cybermen and broke one of Doctor Who's cardinal rules. Very, very action movie-ish, once you get past the slow first part, but in a good way. And the new Cybermen are pretty imposing in this story.
• "Caves Of Androzani." Davison's last story is also his best, by several orders of magnitude. It's the return of Robert Holmes to writing Who, with one last blaze of greatness. The villains are operatic, the story has a ton of great twists, and the end of episode three is one of the greatest moments in Doctor Who. Period.
• "Revelation Of The Daleks." The least bad Colin Baker story is a weird satire on human mortality, set in a funeral home with more than one sinister secret. This story would be much better if it dropped all pretense of being a Dalek story, and maybe if it didn't include the Doctor. But for what it is, it's pretty fascinating.

Okay, that's my advice for new-Who fans. What do you think?

Ace toy photo by Decepticreeps on Flickr.

Jansen first built an amazingly spot-on recreation of the old-school Police Box shell that hides the Doctor's space/time machine, the TARDIS, out of MDF boards. His pics of the construction of the Police box are pretty inspiring — the lamp housing on top looks perfect, the slanty roof is exactly right, and the corner posts are great. The "Police Box" sign lights up. And then he got the inside of the Police Box signed by former star Sylvester McCoy, who was visiting New Zealand in a play.

Then he created a MAME (Multi Arcade Machine Emulator) console, which plays old video games, and customized it to look sort of like the TARDIS console from the late 1980s. (Admittedly, this part of the reconstruction takes a lot more liberties with the TARDIS than the Police Box part.) Check it out — there's a track ball as well as joysticks. And it's so shiny!

[TARDIS MAME Console via Joystiq]

With Who spinoff Torchwood having made the jump to HD this year, Davies says that that unpleasant experience was enough to make him realize that Who should stay lo-fi as long as possible:

I had a terrible experience on Torchwood. There was a lack of training and there was no extra time or money... We'd have to stop and rebuild the tardis. The flaws would show and it would take a lot of money to fix it. So we won't move to HD while I'm there.

HD 'Who' 'would mean rebuilding Tardis' [Digital Spy]

• Any vehicle from the Star Trek Universe: Dilithium Crystals. This is an element created just for Star Trek that powers everything from the U.S.S. Enterprise to a Klingon Bird of Prey. Dilithium had to be mined, just like we have to drill for oil, and could be hard to come by. Of course, when Star Trek: The Next Generation came out the writers decided to just cheat and make it something that they could make synthetically, thereby killing any future "we're out of gas!" storylines.
• The Time-Traveling Delorean from Back to the Future: plutonium, gas, and/or garbage. Doc Brown's time-tripping Delorean actually has an engine that does run on gas, although when he came back from the future he'd converted the flux capacitor to run on a Mr. Fusion device, thereby eliminating the need for plutonium pellets for driving through the decades. Just toss some trash inside, and you're good to go.
• Anything in the Battlestar Galactica universe: Tylium. In the world of BSG, both Cylon and Human ships run off of a fictional ore called tylium. It's only found on certain planets, and has to be mined, just like dilithium crystals. But unlike the crystals, it also has to be refined and turned into a gasoline like substance. No idea what kind of mileage you get out of it, but it also powers their "faster than light" drives, so it must pack quite a punch.
• The TARDIS from Doctor Who: artificial black holes, radiation, life force... take your pick. The TARDIS in the world of Doctor Who looks like a giant blue phonebooth, and travels through both time and space. However it's actually a sentient being that draws its power from one of several different sources, depending on what season of the show you're watching. In the current incarnation of the show, the Doctor has to stop periodically near a space-time rift and suck up the leaking radiation in order to keep things going. A sort of interstellar pit stop, if you will. Photo by lizardian.
• The Spaceship Heart of Gold from The Hitchhiker's Guide To The Galaxy: a cup of hot tea. The Heart of Gold ran on an infinite improbability drive that took it through "every point in the universe at once" when it was switched on. Not too shabby. All it took was an electronic brain and a good Brownian motion generator, like a cup of tea, and you're off. Probably the cheapest form of travel ever invented.
• Anything in Star Wars: your guess is as good as ours. While you sometimes see strange hoses and gizmos hooked to the ships before they launch, it was never made clear in these movies what they run on. George Lucas apparently never wanted us to get bored by the details, so you could fill in the blanks on your own for this one. Lando was running a gas-mining facility on Bespin in The Empire Strikes back, so maybe he was in the spaceship fuel business. We may never know, so be careful with whatever you put in the tank of your X-Wing.

• As always, extinguish all smoking materials while refueling and be sure to hold on to your receipts. Your own mileage may vary.

Famous names: Tom Baker, Peter Davison, Peter Purves, William Hartnell, Patrick Troughton, Colin Baker, Jon Pertwee, Sylvester McCoy, Terrance Dicks, Robert Holmes, Nicholas Courtney, Sophie Aldred.

Crunchy goodness: 5

Memorable product tie-in: The Daleks, mutant nazis in personal super-tanks, spawned a zillion types of crap, from a plastic zip-up playsuit to remote control wheelie Daleks to Dalek Sky-Ray ice lollies. (An ice lolly is like an ice-cicle.) Embarrassingly, a shitload of toy Daleks actually appear in longshot in the story Planet of the Daleks, as an army of super Daleks preparing to conquer the galaxy.

Design breakthrough: Doctor Who pioneered the art of filming in front of a greenscreen — but didn't exactly perfect it. More successful were John Friedlander's latex masks (Davros, the Ogrons, the Draconians) and Delia Derbyshire's pioneering all-electronic arrangement of the theme music.

Life lesson: It's not murder if you trick the bad guys into blowing themselves up (in, like, every episode.)

Outpost Gallifrey