CBS, 9:00 pm ET
If you ve been wondering whether this show's animals make diplomats exempt from attacks, the new episode "The Contingency" dispels that notion. The Russian Embassy in Washington, D.C., becomes the target of the latest assault -- and Mitch and Jamie (Billy Burke, Kristen Connolly) are there when it happens. Jackson's (James Wolk) questions get answers at last, but not from someone he expected to furnish them. Ken Olin and Joanne Kelly continue their guest roles.
CBS, 8:00 pm ET
First Lady Michelle Obama appears in "Homefront," as Gibbs (Mark Harmon) and the wife of a Marine visit the White House for a roundtable that also involves other spouses of military members. The story promotes the "Joining Forces" initiative founded by Mrs. Obama and Dr. Jill Biden. Elsewhere, Vance and Fornell (Rocky Carroll, guest star Joe Spano) go to London seeking a spy on the run. Reiko Aylesworth ("24") also guest stars.
America's Got Talent
NBC, 8:00 pm ET
The competition to see which entertainer winds up with a cool million dollars, plus bragging rights as the most talented act in America (2016 edition), enters its next phase as round one of the live "Semi Finals" kicks off at the Dolby Theatre in Los Angeles. After the first group of semifinalists performs tonight, the lucky five who will advance to the finals will be revealed in Wednesday's live show. Viewers also will have one last chance to send a favorite act to the finals by using Google Instant Save. Nick Cannon is the host.
Pretty Little Liars
FREEFORM, 8:00 pm ET
Call it soapy, melodramatic and pulpy if you like, but this guilty pleasure of a series almost never fails to deliver when it comes to a satisfying cliffhanger. While we have few story details in advance of this week's summer finale, "The DArkest Knight," a Freeform press release promises that "all hell breaks loose" as the Liars find themselves forced to confront some of their old foes face to face. Troian Bellisario, Lucy Hale and Ashley Benson star.
FOX, 8:00 pm ET
Aida Turturro ("The Sopranos") guest stars as an inmate in a women's prison, where an undercover Amy (Melissa Fumero) tries to gather information on a case, in "Maximum Security." Holt (Andre Braugher) and the other detectives stage a ruse of their own, involving a phony funeral, to try to get the goods on a professional killer. Andy Samberg, Terry Crews, Stephanie Beatriz and Chelsea Peretti also star.