Mere hours remain before enemy forces topple the Estonian government and reclaim the country for Russia. Without Langley’s backing, Berlin Station acts alone in one final desperate push to prevent the fall of a nation.

Tina, discouraged by not being asked to prom by Jimmy Jr., forms an unhealthy attachment to a goose from the nearby park. Meanwhile, Linda joins a dating app to help Gretchen find a match.

Mother Mildred returns to Nonnatus while Nurse Crane is in hospital receiving treatment for her back. With help from Trixie, she provides care for a retired dock worker whose former job has taken its toll on his health, only to discover his son may be suffering from a more severe condition. However, her insensitive manner angers the family and they refuse to let her help them.

Peter is mistakenly identified as transgender, which leads to an unexpected event and an important learning lesson.

Ayasha and Doc, a BDSM-inclined couple, decide to start trading sexual experiences for money in their relationship. After discovering he’s internationally known, The Guy pays a visit to a pair of summer-school teachers who have just begun an affair.

When a group of American missionaries become hostages during a violent uprising abroad, Dalton must confront demons from his past in order to help Elizabeth secure their safe return home. Also, Stevie takes over Russell’s social media presence, and Henry helps his niece, Sarah, mentally prepare for her military deployment.

As the team continues to search for a terrorist cell in Los Angeles, Callen and Sam remain trapped in a movie theater after multiple bombs have detonated and every remaining exit is wired with explosives.

The finals of the Hobo Games have arrived, and Frank faces off against his friend and greatest opponent while Ingrid grows anxious about his commitment to their future family. Lip prepares to officially adopt Xan, but his plans collide with Fiona’s partying. Debbie starts developing feelings for someone surprising, and Carl excels at the shrimp shack.

With his P.I. shingle newly hung outside his office, J'onn welcomes new clients. Trying to take her mind off what happened at the DEO, Kara decides to team up with J'onn on his latest assignment, which unfortunately ends up tying directly into Alex's current investigation that involves the villain Menagerie. Meanwhile, Lena shares some news with James, but his reaction isn't what she expected. Nia invites Brainy to her Valentine's Day party.

Krusty reveals the untold story of his past in his movie "The Sands of Space." While working as personal assistants on the movie, Bart and Lisa learn about the early years of their parents' relationship.

A new arrival at the Hilltop opens up about the leader of a group of mask-wearing savages. A search party sets out on a daring mission to find two missing friends.

Matt LeBlanc and Chris Harris head to Norway in the latest estate cars from Porsche and Ferrari, while Rory Reid and Sabine Schmitz aim to create Britain’s newest mountain with the help of a tiny Suzuki. James Marsden is the studio guest.

Following up on new leads, Wayne and Roland track down a man who left the police force in the midst of the Purcell investigation. Meanwhile, Amelia visits Lucy Purcell’s best friend in hopes of gaining insights into the whereabouts of the mysterious one-eyed man.