Dr. Wolf helps a ballerina recover after a mystery illness; the team tries to save Sam's life and get him on the transplant list; secrets are revealed at the hospital's annual holiday gala that change the course of the doctors' lives.

Trump spent the weekend celebrating Thanksgiving the traditional way: abusing reporters, calling Tim Walz the R-word, and bragging about his "perfect" MRI score. Plus, while the president spins a National Guard shooting for his anti-immigrant agenda, Jon Stewart slams the double standard of criminal justice for immigrants and J6 insurrectionists. Pulitzer Prize-winning author and staff writer at The New Yorker, Elizabeth Kolbert, sits down with Jon Stewart to discuss her latest book, "Life on a Little-Known Planet: Dispatches from a Changing World." They talk about matching the awareness of climate problems with an effort for change, humans wasting 10,000 years of "climate stability" by inventing ways to disrupt it, the Trump administration's climate policy regression, and how developing countries are reaping both financial and environmental gains by leaning into clean energy.

1. Zoe Saldaña ("Avatar: Fire and Ash"). 

2. Paul Anka ("Paul Anka: His Way" and "Inspirations of Life and Love"). 

3. Musical Guest Paul Anka.

Guests include Sydney Sweeney, Tom Pelphrey and musical guest Alex G.

Lady Gaga takes "The Colbert Questionert."

New Jersey Governor-elect Mikie Sherrill.

Performance by Kristin Chenoweth and Stephen Schwartz from the Broadway production of "The Queen of Versailles."

Special appearance by Daniel Craig.

Zoe has some difficult questions for a loved one, Anthony collects evidence, and Nicola tries to protect Harry.

Ste tries to do the right thing, but a text leads Lucas to jump to conclusions. Elsewhere, a resident fights to keep the past hidden and Liberty tries to pull her family back together.

Ray and Celia discuss their plans, Dylan is horrified and Paddy admits how much he misses his dad.

Another Christmas day in the Big Brother house and more shenanigans. Coco must invite two guests to Coco's Christmas Cafe...can she serve them up without getting caught? And a new shopping task begins...housemates have 30-seconds every time Big Brother jingles his bells to get dressed in their Christmas outfits and sing a Christmas Carol. Housemates get to watch as Ed gives his two live nominations. Vinnie calls Ed out on his speech about him. And in the middle of the night, one last Christmas Carol sends another housemate out the door!

Paul gets elephant treats. Red panda cubs are trained for breeding. Western Plains Zoo has a baby boom of quokkas, giraffes. Vets treat a sea eagle's fractured wing, and Uma the bush stone curlew trains for free flight.

When a U.S. naval officer is arrested for murder while trying to destroy a treasure map, the team must navigate jurisdictional politics to uncover the truth while racing to find the fabled "Yamashita's Gold,".

Zac's reputation goes up in flames. Paul's mysterious plans loom closer. The Varga-Murphys face an uncertain future.

David turns back the clock and reimagines some dinner party classics for guests Brie Larson and Courtney McBroom.

Actor George Clooney talks "Jay Kelly" with Michael Strahan; Bluey and Bingo ("Bluey"); Holiday Prep! with "Half Baked Harvest" cookbook author Tieghan Gerard; Holiday Gift Guides for the whole family with President and CEO of Duluth Holdings Stephanie Pugliese and "GMA" lifestyle contributor Lori Bergamotto; Deals & Steals: Giving Tuesday with ABC e-commerce editor Tory Johnson.

Once at the enchanting safari, the trio faces nonstop challenges — from a river crossing to a drawing contest, charades and a mafia game to end the night.

The mafia game sparks suspicion, cunning and shakedowns. The next day, the trio heads out on a magical safari drive before a Korean meal — with a twist.

After an awe-inspiring hot air balloon ride and a poetic picnic, the trio face their final game — a trek across the resort to find the elusive giraffe.

Hidden Heroes. No Kid Hungry Holiday Toy Drive. Catching up with Dave Coulier. Jamie Lee Curtis on "Ella McCay." Walmart Gifting with Makho Ndluovu.

Jordan Klepper, host of THE DAILY SHOW.

NOTE TO SELF: John Driskell Hopkins, member of Zac Brown Band.

CollegeHumor alums Hayley, Pat, Brian, and Nick drink Lake Erie slushes and learn some new things.