The Bletchley Circle: San Francisco, STV, 9pm

THE drama series about a group of female former Second World War codebreakers who use their ability to spot patterns to solve complex crimes proved so popular, it even spawned this spin-off, in which two of the women – Millie (Rachael Stirling) and Jean (Julie Graham) – went sleuthing in San Francisco. The first episodes were shown last year, and now it’s back for the rest of the run. It begins as a badly-beaten stranger shows up on Millie and Jean’s door, begging for help from Millie’s cousin Edward, who insists he has no idea who the man is. The stranger disappears again, but when Hailey later discovers heroin amongst his possessions, it plunges the women into a dangerous underworld, and forces them to work out the pattern behind a series of attacks if they are to avoid becoming the next victims.

Cruising with Jane McDonald, C5, 9pm

THE first of a two-part Indian adventure finds Jane amid the colourful chaos of the city of Kolkata, where she visits the largest flower market in Asia, before being treated to a ringside view of some traditional wrestlers in action. Jane then sets sail on India’s most holy river, the Ganges, on board a five-star ship.

The Looming Tower, BBC2, 9.30pm

IN the aftermath of 9/11, many people were left wondering if more could have been done to prevent the horrifying attacks. This new drama series, which is based on Lawrence Wright’s Pulitzer Prize-winning non-fiction book, looks at the FBI and CIA agents who were dealing with the rising threat of al-Qaeda in the late 1990s, and asks whether the rivalry between the two agencies may have inadvertently set the scene for the tragedy. It begins in 1998, as a seized al-Qaeda computer drive arrives at the CIA HQ in Virginia, where section chief Martin Schmidt (Peter Sarsgaard) doesn’t share its contents with the FBI.

Rick and Morty, E4, 10.55pm

THE second series of the animated sitcom begins with a chaotic episode in which Rick decides to unfreeze time six months after it was stopped. He warns his grandkids, Morty and Summer, that time could initially be unstable, but their uncertainty tears time apart into two realities.