Royal revelation for Sir Derek
Veteran actor Sir Derek Jacobi discovers a connection to royalty in the new series of Who Do You Think You Are?, which will also feature Bake Off's Paul Hollywood, choirmaster Gareth Malone and model Jerry Hall this year.
The long-running genealogy show is returning for a 12th series on BBC1 this summer.
Hall, Sir Mick Jagger's ex, will examine her family's pioneering past, from the cotton mills of Oldham to the plains of Texas.
In another episode, Vicious star Sir Derek unearths an unlikely connection to royalty as he examines his roots from Walthamstow in north-east London.
He discovers that his family tree hides a "dangerous secret", with an ancestor leading a double life and travelling to England from the court of Louis XIV of France.
"His ancestor is leading a double life and flees to England where there's another surprise in store - an unlikely connection to royalty on this side of the Channel," a spokesman for the show said.
This year's 10 celebrities also include BBC journalist Frank Gardner, who was left paralysed after being shot in Saudi Arabia, Sir Derek's Last Tango In Halifax co-star Anne Reid and former Bond actress Jane Seymour.
Stage and television actress Frances de la Tour, Sherlock star and co-creator Mark Gatiss and TV presenter Anita Rani also feature in the series, which will see celebrities travel from the Tower of London and the Scottish Highlands to Tunisia, Tasmania, the Punjab in India and the wild west in the US.
Production company Wall to Wall's executive producer Colette Flight said: "Who Do You Think You Are? is back with another fantastic line-up of much-loved faces, uncovering hidden history by bringing our celebrities' ancestors to life.
"Following our best-known stars on their personal journey into their family trees reveals extraordinary stories, sometimes tragic, sometimes funny, but always compelling."