MODERN FAMILY: Andy's girlfriend, Beth, is in town stirring up a whole lot tension with Haley which finally leads to a realization that may have come too late, on the season finale of "Modern Family.” (Tony Rivetti/ABC)

(All times Eastern)

RETURNING SHOW: Forty of America’s best home cooks present Gordon Ramsay their signature dishes for a spot on “MasterChef” (Fox at 8 p.m.) Season 6. The winner will receive a cookbook deal and a $250,000 grand prize.

FINALE WATCH: With $1 million at stake, the castaways spend their final days on the “Survivor” (CBS at 8) island before facing their last tribal council. Following the finale, there will be a live reunion show which, as we all know, is where all the juicy stuff goes down.

SERIES PREMIERE: A game show for self-described “geniuses,” “500 Questions” (ABC at 8) features highly difficult questions for its players from across the country. The show will run nine consecutive nights.

FINALE WATCH: Picked up for a second season,“The Mysteries of Laura” (NBC at 8) ends its first with Laura in hot pursuit of Jake’s shooter.

FINALE WATCH: The “Law & Order: SVU” (NBC at 9) Season 16 (it’s been renewed) closer has Noah’s adoption in jeopardy, and Benson fearing for his future.

FINALE WATCH: On the 10th season closer of the renewed cult favorite “Supernatural” (CW at 9), Dean makes a stunning decision that not only affects his life but Sam’s as well.

FINALE WATCH: Two ABC comedies that will be back for more episodes, “Modern Family” (ABC at 9) and “Black-ish” (ABC at 9:30), wrap up their respective seasons with Phil using a robot to Skype himself into Alex’s graduation party, and Jack and Diane digging into family history.

FINALE WATCH: “Chicago P.D.” (NBC at 10), which has been renewed, closes its second season with Voight and the team rescuing retired Cmdr. Perry’s nephew from a corrupt squad.

RETURNING SHOW: On the fourth-season opener of “Celebrity Wife Swap” (ABC at 10), Emmy-winning actress Jackée Harry trades lives with John Waters muse Traci Lords.

FINALE WATCH: With little information as to what to expect for his last show, except ample surprises and musical guests, “Late Show With David Letterman” (CBS at 11:35) signs off for good.

Actor David Duchovny and comedian Jeff Foxworthy are on “The Tonight Show Starring Jimmy Fallon” (NBC at 11:35), with musical guest Pitbull and an appearance from former “Tonight Show” bandleader Kevin Eubanks.

On May 20, David Letterman will host his last show, ending a 33-year career on late-night television. Here are some of his top moments from CBS's "The Late Show with David Letterman" and NBC's "Late Night." (Jayne W. Orenstein/The Washington Post)

A repeat “Jimmy Kimmel Live” (ABC at 11:35) (because who wants to compete with Dave?) brings out country star Tim McGraw and actress Patricia Heaton.

— Rachel Lubitz