What show was the WORST EVER about constantly shifting directions?

Sometimes TV shows bore us by trotting out the same formula in every episode. But some go to the other extreme, changing the setup and characters so much that it's like plot whiplash every week. What show was the worst offender in the "constant changes" department?

Please be sure to include clips, pictures, or links! That makes it ever so much more fun for those of us who are watching from home.