About 24
24 is a thriller that is shown in "real-time," with each minute of airtime corresponding to a minute in the lives of the characters. Commercial breaks were originally placed at times when non-essential plot is taking place (i.e. characters driving somewhere will begin when a commercial break starts and arrive at their destination at the end of the commercial break.) This allows for the show to actually occur in real time without compromising action.Actual show run time without commercials is about 45 minutes, as is typical for hour long television shows on many commercial stations. However, the effect only works if episodes are shown with commercial breaks during the show (which, for example, is uncommon for public television stations in Europe), and then only if these are inserted at the right points in time and have the exact right length, which may not fit in with the normal programming of a commercial station.
Watched continually each season would take approximately 18 hours to finish. This real-time nature is emphasized by an on-screen digital clock appearing before and after commercial breaks, with a distinct beeping noise for each second, alternating between C and D tones. This time corresponds to the in-universe time of the show. The characters will often place time windows (such as the common "within the hour") on certain events such as terrorist threats, thus strongly hinting that the attack/event will occur before the end of the episode.
The action switches between different locations tracing parallel adventures of different characters involved in the same overarching plot. As a result, there may be long sections of unseen narrative for each character; in that case, a character may only be seen for a portion of an episode's overall running time.[
About the Cast
24 is known for making major changes to its main cast every season — the sole exception being Kiefer Sutherland, who is the only main cast member to star in all six seasons to date. Honorable mention should be given to Glenn Morshower who plays Aaron Pierce - the only actor besides Sutherland to appear in all six seasons. Due to the unpredictable nature of each season's storyline, main cast members are added and dropped frequently. In a few cases, guest stars have been upgraded to main cast members during the course of a season. Main cast members who return from prior seasons — whether they return for one episode or the better part of a season — are often given a "Special Guest Star" billing, although this is also used for other cast members who are well-known film actors, like Dennis Hopper, Powers Boothe, Sean Astin, and James Cromwell.Because of the intense nature of the series, the number of onscreen deaths is high compared to other television dramas. Of the 28 characters who have comprised the main cast over the past six seasons, ten are deceased. That number is considerably higher when guest characters — whether they be government agents or terrorists — are also included. Whenever there is a death of a character, there is always a reason for it, for storytelling's sake, and it always relates back to Jack in some way.
[Wikipedia.org]