* American Idol (9 pm/ET Fox)
There was Vegas swing and sway last night when the Top 5 interpreted standards popularized by the Rat Pack, the 1960s clique of cool crooners that included Frank Sinatra, Dean Martin and Sammy Davis Jr. All this happened sans Anoop Desai and Lil Rounds, who lacked disco fever the week before and fell victim to a double gonging. Now the lasting quintet - Kris Allen, Matt Giraud, Danny Gokey, Allison Iraheta and Adam Lambert - anxiously await viewers' verdicts on last night's performances, with one of them ultimately heading home. And alert the Soul Patrol: Season 5 winner Taylor Hicks returns to Idol to perform "Seven Mile Breakdown."
* Lost (9 pm/ET ABC)
Now that we know about Miles - he talks to dead people, his dad is Dr. Pierre Chang, etc. - we can move on to the other surviving member of the Widmore island expedition (other than pilot Frank Lapidus): Daniel Faraday, who was just alighting from the sub in 1977 as the last episode ended. It appears that the time-defying physicist has arrived just in time for Dharma's hostilities with the hostiles to heat up. In fact, don't be surprised if his presence has something to do with triggering them.
* Legacy of War (10 pm/ET PBS)
Legendary newsman Walter Cronkite, who covered the aftermath of World War II in Europe some 60 years ago, revisits such locales as London, where he reported on its postwar rebuilding initiative; the Nuremberg courtroom where he witnessed the trials of war criminals; and Berlin, which quickly became a Cold War symbol. Along the way, he details the long-term implications of that era, from fueling the baby boom to leading to the emergent U.S. role as a superpower.
* CSI: NY (10 pm/ET CBS)
Edward Asner guest stars as Abraham Klein, a clockmaker who survived Auschwitz, in an emotion-charged episode that includes brutal images of the Holocaust. The mystery begins when a jewelry appraiser is murdered during a lucrative auction. The routine case suddenly gets complicated when it's discovered that the victim was both knifed and shot in the same place on his body, and that the bullet that killed him is German-made and dates back to the 1940s.
* Criminal Minds (9 pm/ET CBS)
Fans of the canceled drama Moonlight will be happy to see actor Alex O'Loughlin return to the network, if only for one night. O'Loughlin plays a serial killer who sends a video documenting one of his crimes to the BAU team, but it's not to taunt them - or even part of his twisted MO. The agents learn that the man is sending them a message to help him stop his murderous spree.