Who Do You Think You Are? (BBC1, 9pm)

ACTOR, comedian, author and presenter David Walliams is the latest famous face to trace his lineage in the genealogy series, and he’s delighted to learn that being an entertainer runs in his family. Travelling from his home town in Surrey to the First World War battlefields of Belgium he finds out more about his great-great-grandfather who, after becoming blind, forged a new career as a travelling entertainer. A more tragic story emerges, however, about his paternal great grandfather’s experiences – he suffered such severe combat PTSD (or “shellshock”, as was the term) that he couldn’t go back home to his young family.

The Billion Dollar Art Hunt (BBC4, 9pm)

IN 1990, the Isabella Stewart Gardner Museum in Boston, Massachusetts, was the scene of one of the most audacious art heists in history, with 13 artworks worth half-a-billion dollars in total removed overnight. In June of last year, journalist John Wilson received a tip-off: that the haul – now worth $1bn – was about to be recovered from a house in Dublin. What happens next is the stuff of movies, but is all true, and is told here in detail.

Police Suspect No 1 (C5, 9pm)

THE blue-light documentary following the work of police officers and detectives as they try to gather evidence and secure convictions concludes tonight. A man in Norwich is severely injured in a single-punch attack but no witnesses are willing to come forward. There are similar problems with an alleged robbery outside a bookmaker’s in which a pensioner is injured – no-one seems able to identify the suspect.

The Million Pound Cube (STV, 9pm)

SATURDAY’S celebrity version introduced this new series, updating Phillip Schofield’s game show, which ended in 2015, with a new, big-money jackpot. There’s another big change to the format, too, as contestants take part in pairs rather than going solo. As before, the challenges seem straightforward but they are rarely as easy as they seem and when taking place under extreme pressure inside the confines of the titular box can suddenly become downright fiendish. With a cool million now at stake, the pressure is even greater.