Kelso babysits his daughter for the first time and is worried he is doing something really wrong because the baby will not stop crying.

The remaining 16 finalists have performed in hopes of winning America's votes. Now the viewers have decided who will continue in the competition and who will not. Tonight, four contestants - two males and two females - will go home, leaving America's Top 12 finalists vying for the American Idol crown. The voting results are revealed.

Sydney and Dixon try to prove that Sloane is double crossing the CIA by by using APO to take the Blackwell Index, and is trying to reconstruct the Alliance. Sydney inspects Sloane's house, but when Nadia finds out, she isn't too happy. Meanwhile, Vaughn finds out news about his father, when he visits his uncle.

Using a specially fabricated chamber complete with two-way mirror and a hidden camera, Kari, Scottie and Tory set out to see whether a yawn, like a cold, truly can be caught. Next on the docket: Does toast really fall buttered-side down? Jamie and Adam are on the case, each building a rig to simulate toast being dropped from the dining room table. Finally, the whole team tests the myth that a toy car can beat a real car (in this case, a Dodge Viper) in a gravity slope race.

Super Tuesday is approaching, and Santos flies to Sacramento in order to prepare -- if Santos fails to do well in California, his campaign will be over. While in Sacramento, Santos continues to work to push his health care agenda while he receives pressure from the press to take a stance on California's legislation that would provide driver's licenses to illegal immigrants. Meanwhile, Russell decides not to travel to California; Donna tries to figure out why Hoynes refuses to campaign in California, then takes a bigger role in the Russell campaign by becoming the new spokeswoman.

The finalists are taken headfirst into their first challenge, a dramatic photoshoot where they pose as aliens taking over LA.

One girl's attitude worsens during the makeovers when she is told she will not be having one. Tyra gives her a hair raising alternative.

Paris and Nicole are interns at a day-care center.

Mr. Garrison decides to get a sex change operation, a vaginaplasty which prompts Kyle to want a negroplasty so he can be tall and black enough to play basketball.

TONIGHT: Actor Bruce Willis talks about his new movie, "Hostage".