What to Watch Sunday: Downton Opens Season 3, Good Wife, Revenge and Once Return and More

Downton Abbey Season 3 SpoilersOn TV this Sunday: Downton Abbey‘s Dowager Countess & Co. are back, Jillian Michaels returns to harass encourage The Biggest Loser, there are no Happy Endings for Alex’s pet and T.R. Knight brings some Grey’s matter to The Good Wife. Here are 10 programs to keep on your radar.

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2 pm – 8 pm Nashville marathon (CMT) | Catch up with Rayna, Juliette, Scarlett and their guys before ABC’s country-music drama resumes its freshman run (this Wednesday at 10 pm).

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8 pm Once Upon a Time (ABC) | In Storybrooke, Regina is accused of murder and only Emma believes she may be innocent. Meanwhile, in the fairytale land that was, Snow and Prince Charming plan the Evil Queen’s public execution. (Read preview from Colin O’Donoghue aka Captain Hook and Josh Dallas, check out some photos and watch video!)

8 pm The Simpsons (Fox) | Singer Tom Waits lends his voice to an episode in which Homer, fearing the end of the world is nigh, joins some doomsday preppers getting ready for life off the grid.

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9 pm Downton Abbey (PBS) | Season 3 premiere: Wedding guests – including Cora’s freewheeling American mother Martha (played by Shirley McClain), who tries to loosen up her in-laws — descend on the estate. (If you need it, here’s a quick catch-up on Seasons 1 and 2.)

9 pm The Biggest Loser (NBC) | Season 14 premiere: The weight-loss competition is back with 15 adults (who’ll hop on the scale every week) and — for the first time in its history — three kids (who won’t). Oh, and Jillian Michaels is back, too.

9 pm The Good Wife (CBS) | Michael J. Fox returns as Louis Canning, who’s trying to delay a deposition crucial to Will’s argument in his latest case. Meanwhile, T.R. Knight (Grey’s Anatomy) guest-stars as a political advisor who joins Eli on Peter’s campaign.

9 pm Revenge (ABC) | Victoria’s got a new scheme, and it involves Emily (run, Ems!); Declan discovers something that may threaten The Stowaway’s future. (Read preview and get a sneak peek!)

9 pm Family Guy (Fox) | Somehow, Chris’ trip to Space Camp sends the Griffin family into actual space.

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10 pm The Mentalist (CBS) | The CBI team looks into the death of a young model who was checked in at a high-end rehab center – 24‘s Mary Lynn Rajskub guest-stars as another patient – and Lisbon intensifies her investigation of Tommy Volker (Henry Ian Cusick).

10 pm Happy Endings (ABC) | Brad and Penny accidentally kill Tyler, Alex’s racist parrot. Can the “birderers” cover the crime before she gets home? (And yes, there will also be new episodes on Tuesday, too; 666 Park returns in the summer.)

Hit the comments with your must-see picks from tonight’s lineup!