Definitely Day 5 for me. That season was action packed from start to finish. They wasted no time getting into the plot, which was very intense and surprising, and the ending was crazy! Plus Logan's character was ingenious and was the villain you love to hate. I usually root for the bad guys but I really despised him by the end of the season. And who can forget that Silent Clock with Edgar? No way you could watch that episode without having a reaction. Next on the list would have to be Day 7, Tony was back in full effect and Renee was an excellent sidekick to Jack. 3rd would have to be Day 1, even though it was a little over the top with the Kim Bauer moments, David Palmer's story with his family was very entertaining and the character development of Tony from nosy co-worker to take charge and get things done attitude was classic.
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