24 was always tangled up in current events, tying it's terror-group-of-the-season to what was going on in the allegedly real world, and being accused of making government-sponsored torture seem a foolproof way of getting accurate information.
But what made the show a hit was the stylization: the brilliant real-time concept. Every episode started and ended on the hour, and a clock ran down the time. The creators used this device in many creative ways, playing against the viewer's expectation that the show would end on a moment of high drama. Sometimes it did; sometimes the drama happened and the clock kept ticking...
Counter-terrorist operative Jack Bauer was the only person guaranteed to survive each episode and supposedly the other actors hated to see a scene in which they left headquarters in Kiefer Sullivan's company, because they knew their character might never get back alive. Somehow they never got around to bumping off Chloe O'Brien, the grumpy nerd who kept Jack alive through dozens of dark and dangerous corridors and alleys.
And they never did explain when these people found time to go to the bathroom.