Not only did last night's episode of Fringe have some great nipple commentary, occasioned by a virus that Hulks people out, but it also brought us some closure on a big mystery.

Called "The Transformation," this episode had the usual creepy scares and thrills - including what has now become a little bit of a cliched scenario on Fringe, where a suspect goes virusy while being interrogated by Agent Olivia and the scoobies. Our virus of the week was something that causes people to Hulk out. First they get nosebleeds, then they turn into spiney monsters, then they kill everybody. Then they die due to mega-mutation.

There were some fun scenes of Peter and Olivia going undercover to catch a bad guy named Conrad who is selling the Hulk Virus - apparently "just because he can." I love a bioterrorist who does it for fun, though of course that sort of makes him more like a serial killer than a terrorist. Usually terrorists have some kind of political motivation, and it seems Conrad and his gang were just making and selling this stuff for the highest bidder. That also means they probably aren't part of the Pattern, but somehow overlap with it a little bit. Somebody please make me a Venn diagram of the Pattern, in which one circle is for "bioterrorists who do it for fun," and another one is "secret undercover quadruple agents who work for the NSA and private industry." Not sure what the third circle should be.

Anyway, Olivia is a super badass as usual, and gets the terrorists. But the more interesting part of this episode was the re-emergence (yay!) of shady biotech company Massive Dynamic and my imaginary girlfriend, Massive Dynamic VP Nina Sharp.

A few episodes ago, we learned that Nina had kept Olivia's ex-boyfriend John Scott's body in a state of undeath so she could attempt to read the memories in his brain. Unfortunately, all those memories had been transferred to Olivia's brain during one of mad scientist Walter's undead psychic experiments with the isolation tank. The isolation tank (which means "Olivia in cute undies") was in heavy rotation last night because Olivia keeps seeing John's memories of the terrorists they're tracking. Olivia also discovers that the Hulk Virus terrorists all have little glass floppy disks implanted in their hands "from the NSA." Knowing that John worked with these terrorists - based on her memories - Olivia demands that bossman Broyles exhume ex-bf's body.

And finally Broyles has to reveal that Nina still has John Scott's body. Nina says they kept him around to try to read the glass floppy in his hand, because the disks self-destruct when their host dies. BUT! You and I and the other Fringe fiends know that they actually kept John to read his BRAIN, not the disk. So Olivia still only knows part of the deep truth.

While she's tanking out and talking to the John in her head, Olivia also learns that maybe John was a good guy after all. He says he was a double-super-secret NSA agent, who was working undercover with the bioterrorists to ferret out Conrad. Could the John in Olivia's head be lying? Honestly, it's hard to say. No matter what you and I think, Olivia feels much better about getting it on with John now that she thinks he's a good guy again. They share a tender moment where they say "I love you," and then Walter confirms that the John parts of Olivia's brain have been purged. So the John in her head is dead, but he's left a warm schmoopy feeling behind.

Still, his undead body remains at Massive Dynamic. I predict more John in future episodes. Also, what about these other super-duper-secret NSA guys he supposedly worked with undercover on the Conrad case? Will they be back, too?

All I can say is that right now, a bunch of NSA agents are slapping each other on the backs and saying, "Dude, this show makes us look totally awesome. What we really do is work in basements writing reports about signals intelligence, but on Fringe we like kick ass and fight Hulk Viruses and crap."

Also, as a super-duper-secret person asked me today: When are we going to find out that Olivia's partner Charlie is a double agent? To which I add: Or a quadruple agent? Sextuple agent? Is there a way to figure out how many layers of super-agent you are by counting your nipples?