Jon Hamm, Mad Men Jon Hamm, Mad Men

Mad Men
10 pm/ET AMC
In the engrossing second season finale, the staff is agog over questions and speculations as to why Don is AWOL in California. One school of thought believes there's an "aerospace gold rush" and that he's out to land a big account. Another concern is that he's "breaking off and opening his own shop in L.A.," while a third thinks he's location hunting and hoping to find "a good spot for Sterling Cooper West." Back on the home front, Betty receives some unsettling news. — Ray Stackhouse

For full episodes of Mad Men, visit our Online Video Guide.

Amazing Race 13
8 pm/ET CBS
The seven remaining teams travel from New Zealand to Cambodia on the fifth leg of the race and major problems ensue: One duo gets in trouble with the law while driving, and another pair's boat develops engine trouble during a race on water. Will tonight be another elimination point or will it be the first non-elimination pit stop of the race? — Tim Holland

Relive all the Amazing moments from seasons past in our Online Video Guide.

Desperate Housewives
9 pm/ET ABC
The Wisterians have made quite a leap this season — five years, to be exact — and tonight's episode fills you in on some of what happened in the interim. In the present, look for more trouble in the Scavo household, this time involving the pizzeria. Meanwhile, it's Mrs. McCluskey's 70th birthday, and Dave wants Susan to throw her a surprise party. This might not be a good idea. — Paul Droesch

For full episodes of Desperate Housewives, visit our Online Video Guide.

True Blood
9 pm/ET HBO
Let's leave aside for a moment the fact that Sookie is afraid Bill might have been killed (again), in a conflagration of redneck revenge. Instead, witness the remarkable turnaround of Lettie Mae, which makes Tara take another look at exorcism, and Jason's latest girlfriend, Amy (Lizzy Caplan), who dismantles his lunkhead facade to the point that even he believes it. Of course, that could just be the "V" talking, because you won't want to miss what Amy's got up her sleeve when her stash runs out. — Joe Friedrich

For clips of True Blood, visit our Online Video Guide.

Entourage
10 pm/ET HBO
Let's not forget the touching moment — especially for Entourage — between Vince and Ari at the airport last week. But proving that word travels fast in Hollywood, the studio's courting of Ari is making headlines before his plane from Geneva even lands. Well, what follows tonight is one "what if?" after another, and it's another good sign that this show is back in first-class form. Speaking of first class, Turtle lucks into an airplane seat next to Jamie-Lynn Sigler, but his recollection of the experience doesn't fly with Drama. — Joe Friedrich

For full episodes of Entourage, visit our Online Video Guide.