In the fleet's last push for gold, Reaper Nation fights to mine until the cold, bitter end. Shawn reaches for gold in deeper waters. Emily must depend on her last remaining diver. Chris and Zeke debate whether to mine in murky conditions.

New business ventures take shape for the Thomas family, but the outlook is bleaker for the Mathis brothers as Ronnie's patience runs out. Raq makes a risky move for Kanan's obedience.

When Nebula is recruited to join the Nova Corps, she sets out to prove her detective skills.

A glitzy tech launch turns into a disaster, leaving half of NCIS: Sydney trapped underground, and the others scrambling to save the day before the clock and the oxygen runs out.

Magicians Benjamin Barnes, Hara, Helen Coghlan, and Daniel K try to fool the veteran duo with their illusions.

Parker gains momentum at Dominion Creek, but a mysterious gold loss could set him back. Tony moves everyone back to Paradise Hill, and tensions boil over. Rick bets on a mechanic who's never been in a gold mine.

Jimmy gives away a holiday sweater to a lucky audience member in 12 Days of Christmas Sweaters and pens his weekly Thank You Notes before speaking with guests Cynthia Erivo and Kiefer Sutherland and welcoming comedian Jay Jurden for a stand-up routine.

A group on Mars takes drastic measures. Margo grapples with a new assignment.

In 2012, Macchiarini's research gets published after his patient in Sweden is asymptomatic two months post-surgery. In the present, Hannah suffers complications. Paolo and Benita grow closer. Paolo seeks new patients to expand his practice.

Reacher and his team head to Boston to track down a political aide with insider knowledge of a top secret military-defense contract that may be the reason behind their friends' deaths.

May finally faces her past. Duvall and Shaw follow traces of Godzilla and Hiroshi.

A father-son road trip to Niagara Falls gives Eric and Steven some much-needed bonding time. Meanwhile, the Grand Coda's passengers face catastrophe.

Facing financial ruin, Jang Tae-sang agrees to track down a missing person - but two figures trail him. Meanwhile, sinister operations occur underground.

Emma Willis returns to host the semi-finals as the superstar coaches need to take one of their singers through to the final.