When Barry Allen and Oliver Queen wake up one morning and realize they have swapped bodies with each other, the two set off to find out what disturbed the timeline to cause such a shift. However, things quickly go from bad to worse when they present their case to Team Flash and the gang doesn't believe them. Barry and Oliver realize they need Supergirl's help and travel to Smallville on Earth-38 where they end up meeting Kara's cousin, Clark Kent, and intrepid reporter, Lois Lane.

Jamie and Claire are surprised when Lord John Grey drops in on Fraser's Ridge with an unexpected traveling companion. When Grey takes ill, Claire must reconcile her personal feelings with her duties as a doctor.

Summer season at Steiner Mountain Resort continues as Moishe and Shirley join the group, disturbing Abe's peace. Susie tries to ward off a new friend while keeping a low profile at the resort. Midge jumps at the opportunity to redeem herself at B. Altman.

While hiding in Howard's life, Howard Prime must avoid detection at home and at the OI. Quayle and Clare struggle to adjust to their new arrangement.

When the God Account sends Miles the name of one of Arthur's parishioners, a single father who recently lost his wife, the similarities to their own loss reopens old wounds. Also, Rakesh and Cara hunt down a new lead on the reclusive hacker they think may be behind the God Account.

After a failed Black Friday shopping spree, Marge is determined to fix Christmas. However, Homer and the kids surprise Marge with a vacation to a Florida resort.

The battle is on when some angsty teenagers take over Louise, Gene and Tina's usual sledding territory, inciting an epic turf war. Meanwhile, Bob steps in to help Linda, who's in a time crunch to get three scarves knitted before Christmas.

Kim devotes her time and energy to helping free Alice Johnson from prison. Khloé stresses about spending her first night away from True. Kanye finds himself in hot water over some controversial comments.

The Pawtucket Brewery hires new bosses, who decide to change the company's mascot. In an attempt to be crowned the new face of Pawtucket Ale, Peter and Brian go head-to-head.

Mel turns to Harry for guidance after learning information about the magical world that leaves her questioning everything she knows. Galvin shows up to see Macy and she is determined to not let fate get in the way of their potential relationship. Meanwhile, Maggie tries to keep her mom's Christmas traditions going and is excited for Parker to be a part of it.

Elena returns to Naples to find Lila has made a romantic connection with Stefano, despite the looming presence of Marcello.

While Samantha and Brittany attend a speaking event at a children's hospital, it is revealed that Brittany has yet another unique advantage. Vicki tries to find something about Sam that will give her a leg up in the competition, but Sam's true capability is shown after a night's out.

An elaborate bank heist to steal a single safe deposit box held by Veronica Stephens, a Navy contractor, leads NCIS to investigate her corrupt consulting firm.

First into the Tank is a family of entrepreneurs from Chapin, South Carolina, and Fairhope, Alabama, who present a product that satisfies a unique, and some would say disgusting, obsession; husband and wife duo Joanna and David Parker from Englewood, New Jersey, introduce their convenient subscription service that makes meal time for kids stress-free for parents; an entrepreneur from Yorba Linda, California, pitches his Bollywood-inspired dance fitness program that gets the Sharks dancing; last into the Tank is a husband and wife pair from Dallas, Texas, who give the Sharks a taste of their better-tasting probiotic beverage.

With Ray's work on Anita's campaign getting in his way, Mac lays all of his cards on the table. Knowing what his friend is facing, Ray must choose where his loyalty lies. Terry and Darryl bring Bunchy home to Boston to get in touch with their roots. Mickey considers the great white north.

One of Rel's patients is prejudiced and Rel is conflicted on how to behave as his attending nurse. Meanwhile, Brittany, Nat and Dad hang out at Frances', where everyone is obsessing over Brittany's ex-boyfriend's awful new rap song.

Elizabeth and Jay work to keep a historic agreement between Serbia and Kosovo from falling apart, after a mass grave is discovered in Serbia dating back to the Kosovo war. Also, Henry deals with a bizarre encounter with Secretary of Defense Gordon Becker.

When Poe and Kaz find an old First Order mining facility, BB-8 discovers that the facility isn't so abandoned.

Excited by the possibility of a new life, Tilly tries her best to avoid Lyle, who is planning something special for their anniversary. Sweat makes progress on the escape route, but feels like he's doing all the work. Matt likes the arrangement just fine.

Debra discovers John's criminal record. In the past, John starts his first family.

D'Branin and his team explore a more permanent solution to their problem.

As the Murphys and their neighbors scour the city, Bill bounces from one harrowing ordeal to the next. Rosie's debate turns into a rescue mission.

Beau intervenes to keep Colt out of trouble. Abby and Colt follow a lead. Maggie returns to Garrison, and Mary wrestles with guilt.

A Tariq-Amir member set on stealing the clan's throne makes a gruesome bet on the match to secure an ally. Erol ensures the clan sees him with Murad.

Elsa comes unglued when she discovers her friends have been hiding big news from her. Milou has a change of heart about Charlotte's scheme.

The Nowhere Boys take a wrong turn in their quest to find Zeb, landing them in danger and on the run. Meanwhile Ben and Ellen decode clues left by Zeb and try to find a way to bring them home.

Victoria Coren Mitchell hosts the series where knowledge will only take you so far. Patience and lateral thinking are also vital. A team of Welsh descent take on three theatre fans in this opening heat. They compete to draw together the connections between things which, at first glance, seem utterly random. So join Victoria Coren Mitchell to learn what connects Planet Biyo, JD Wetherspoon, Harry Potter's son and Lynyrd Skynyrd.