* Farrah's Story (9 pm/ET NBC)
Farrah Fawcett's battle with anal cancer began in 2006 and continues today. Over the past three years, the 62-year-old former Charlie's Angel star videotaped her thoughts and chronicled her medical treatments in the U.S. and Germany, using her own home video camera. The result is this highly personal account of her life since being diagnosed and becoming a renewed target of paparazzi and tabloids, which she also addresses. Also appearing and commenting are Ryan O'Neal, Kate Jackson, Jaclyn Smith, Alana Stewart (who shot most of the footage) and Jim Fawcett, the actress's father.
* Prison Break (8 pm/ET Fox)
Here's the deal: Christina and Pad Man both have someone Michael wants desperately (the wounded Linc and the pregnant Sara, respectively), and Michael has something Christina and Pad Man want desperately (Scylla). Michael is also being chased by a gazillion cops, and Mahone has his own agenda, so...We'll stop now, except to note that tonight's two-hour series finale is also a Prison Break reunion. (OK, Haywire, Tweener and Bellick couldn't make it back, but you get the idea.)
* America's Funniest Home Videos (8 pm/ET ABC)
In these tough economic times, vacations are often at the top of the list when families need to cut back. In tonight's two-hour, 19th-season finale, it comes down to three contestants who have already won $100,000, a tidy sum that could certainly fund more than a few fancy getaways. But their travel plans would be solved for decades when one of them comes away with the grand prize: a membership in the Disney Vacation Club, which offers the victor a choice of worldwide destinations for 50 years.
* Numb3rs (10 pm/ET CBS)
The fifth-season finale is an emotionally demanding hour in which Amita is kidnapped by a manipulative, self-deluded guru (a scary James Callis, best known as Baltar from Battlestar Galactica) who fancies himself to be a modern-day messiah. Amita is the latest addition to his all-female tribe, but he has a specific mission for her. That mysterious mission becomes Charlie's obsession to figure out so he can locate and rescue Amita before it's too late.
* Ghost Whisperer (8 pm/ET CBS)
With Jim and Melinda finally together again and a wedding on the horizon, it would seem that the fourth season would come to a close on a happy note. But a mysterious visitation by a ghost leads Melinda to fear for the life of her unborn child. Guest stars include David Clennon and Bruce Davison.
* Don't Tell the Bride (8 pm/ET BBC AMERICA)
It takes a brave bride to give her groom free rein in the planning of their wedding, and that's the basis of this British reality series, which gives cash-strapped couples $20,000 toward their big day - but there's a catch, of course. The bride-to-be is separated from her fiance in the weeks leading up to their nuptials, which he'll plan entirely on his own. From the invites to her wedding dress, it's all in his hands. Talk about pressure!