24 (Season 1, Episodes 13-16)

Creator: Robert Cochran, Joel Surnow
2001
This was the quartet of episodes when things cycled back around. Jack was reunited with his family; Jack returns to the office after several hours on the run; Palmer finally confronts Jack; the plot and its motivation is finally explained to us. And almost immediately things began to fall apart. Possibly this structure will be mirrored in the end–we’ll have to wait an see.
Another note: it’s really hard to do research into 24 without running into massive spoilers on the web. There’s been a few times I’ve nearly learned some shocking truth about the ending, only to turn (or click) away in time. Yes, I know it’s not going to end well (and it’s going to be a cliffhanger, but of course). Yes, I know there’s more twists to come–and more death.