Don't get me wrong. 24 is an extremely intelligent, addicting, well-written, and well-acted show. Though it can get very repetative, it is consistently moving and engaging. However, it is an adults-only program that has extreme violence and other graphic content. Going into this show, I thought that its TV-14 rating would be the equivalent of a PG-13. Far from it. The show's graphic content is hard R rated, and I would rather my kids watch certain R-rated movies than this show. Please note, however, that I haven't seen every episode of the show, so the content listed should be considered a minimum.
The show's violence is consistently bloody, graphic, and disturbing. People are shot in every imaginable area of the body with spurting or spraying gore. Also, people are stabbed, exploded, or electrocuted graphically. Dead bodies made gorey with disease are shown. Jack Bauer uses common-place items like books and pens to fight people and often kill them. Main characters with whom the audience sympathizes are frequently killed brutally entirely on-screen. Rape and sexual assault are never shown, but sometimes implied and spoken about. Jack has to resort to gruesome measures to get the information he needs, including digging into people's deceased bodies with his bare hands (squirting blood is seen). Torture is also a main point of the show. Though the show's star, Kiefer Sutherland, is very anti-torture off-screen, the act of torture is never looked down upon in the actual series. People are shot, injected with chemicals, beaten within an inch of their lives, and dismembered (all on-screen) in order to get info. Several people's families (including children) are killed before their eyes. All of these actions are done by authority figures in the government.
Sex is limited to brief implied trysts or flashes of skin (never any explicit nudity). Some extra-marital affairs are spoken about, sometimes quite frankly. "D**n" and "SOB" are used almost constantly, but that's the extent of language. The series also has the R-rated equivalency of drug use. We see people (including Jack) do drugs very graphically and disturbingly. One lady, dressed as a prostitute, is shown nearly nude in a disheveled room, injecting heroin into her foot veins while laughing hysterically (due to being high).
Now, this content alone probably wouldn't get an "off" rating if it weren't for the messages that accompanied it. Though the show features many positive aspects, like sacrifice and bravery, the main message of the series seems to be "no one is incorruptible." Even squeaky-clean characters resort to violence and blackmail in order to get their way, and often get away with it. Jack Bauer keeps no one alive, and leaves a monumental body trail wherever he goes. The movie almost seems to promote the violence and torture it contains.
All in all, this is a good show for adults only. It will only give bad messages to kids. I have no idea how it evaded a TV-MA rating. PLEASE NOTE: The series gets more graphic and violent as it goes on, but once kids start season 1, they won't want to stop due to the show's addictive nature.
What other families should know
Too much violence
Too much sex
Too much drinking/drugs/smoking