Like the usual 24 episodes it centers its drama around a guy kicking butt, using quick camera moves, editing and lots of jumping, sliding and shooting bad guys, but sans Jack Bauer.
Instead of Bauer we follow the adventures of one Jason Blaine (Jeremy Ray Valdez) who is a minor player in the CTU but seems to have a knack for getting himself into dicey situation. Just in the first season he is asked to get just some coffee and ends up foiling a bank robbery. Later seasons deal with more serious terrorist issues and tie small connections to actual 24 seasons and storylines.
As this show is produced by the same people behind the big-budget TV show 24, they were able to reuse sets and locations as well as the production crew and thus creating this 3-season show within the TV show budget. It was meant to tide us over in between the actual 24 seasons. As such, the show delivers. Having these creative TV talents behind helped, so this is by no means a rookie show. It also serves as a good example as to how short episodic action shows should be created and look like.