As Rask slides into a pit of violence and corruption, he fights to regain control. Nick and Izzy absorb a devastating blow to GenCoin. Ronald takes a risk with the company pitch.

Hodiak decides to take matters into his own hands and shows up on the doorstep of the mysterious serial killer who has been sending him obscene pictures. Meanwhile, Manson sends Bobby, Mary and Sadie to go to extreme measures to get money from Gary Hinman.

A newly "retired" Hodiak tracks down the serial killer who has been tormenting him for months, without the protection and authority of his police position. Manson sends Tex, Sadie, Emma and Patty to 10050 Cielo Drive, where they are swept up in one of the most infamous crimes in the country's history.

Pablo is reunited with an estranged family member. Judy Moncada's life is put in danger. The DEA and CIA clash over how to handle Los Pepes.

Bill's cat escapes and he blames Tig for letting her out. Tig's biological father, Mick, leads a search party. Assigned to survey the neighborhood, Tig unearths a secret from Caroline's past. Having found a local station where she can record her show remotely, Tig connects with Kate, the off-beat radio station manager.

Thor teaches the Vision the value of friendship by taking him to Asgard where together they must fight an Ultron-controlled Destroyer.

Tensions arise at Ash Park while Sarah's life hangs in the balance and Carolyn's lifes falls apart. But how will George react when he learns of Regina's plot?

Coming Soon...

Coming Soon...

As the election leads to rioting, Elizabeth goes to Bodmin herself. Demelza tries to influence the case by making a personal appeal to the judge, but George has a number of tricks up his sleeve as the day of the trial arrives.

Prince Albert arrives in England for the first time, and he and Victoria take an instant dislike to each other in an awkward first encounter. Below stairs, Albert's valet clashes with the royal servants, while Skerrett is visited by a girl in need of money.

Comedian Jimmy Carr takes over Horizon for this one-off special programme, produced as part of BBC2's sitcom season.

Jimmy turns venerable documentary strand Horizon into a chat show, with eminent laughter scientists as guests and a studio audience to use as guinea pigs. Jimmy and his guests try to get to the bottom of what laughter is, why we enjoy it so much and what, if anything, it has to do with comedy.

Between them, and with the help of contributions from other scientists on film, Jimmy and guests discover that laughter is much older than our species, and may well have contributed to making us human.

Johnny Vegas joins the gang on Day 4, and there's a special performance from Richard Whitehead ahead of his 200m title defence. Plus, velodrome stars Jody Cundy and Jon-Allen Butterworth.