Every Season of 24 in a Nutshell:

Someone is after Jack Bauer/The President

They are using a terrorist group to get to them

A deadly virus/nuclear bomb/other sort of bomb is about to be unleashed on Los Angeles/New York/The World

Someone in CTU/The Whitehouse/FBI/all of the above is helping the evil terrorists

Oh no! It’s a conspiracy! The evil terrorists are a smoke screen for the real villain!

Explosion

Gun fight

The disaster they've been trying to avert happens

Chloe tells everyone what's really going on. No one believes her.

Jack captured by villains

Jack escapes from villains

Jack Bauer is shot/stabbed/infected with deadly virus. Oh no! Will he live? Of course he will!

Someone Jack cares about is in danger!

Jack disobeys orders to save them

Jack disobeys orders to save Los Angeles/New York/The World

A character reminds everyone that another character is a sociopath

Explosion

Gun fight

Helicopter

They believe Chloe now

Person Jack cares about dies/is deeply psychologically scarred/maimed/leaves the series

Jack saves The President/Los Angeles/New York/The World

He's still in trouble: he didn't get permission to save The President/Los Angeles/New York/The World/A lost puppy...