BBC Four HD SkyTV

Marcus du Sautoy demystifies the hidden world of algorithms, revealing where these 2,000-year-old problem-solvers came from, how they work and what they have achieved. [S] [HD]

Peripatetic gardener Chris Beardshaw flies to the south west in search of hedges. He visits the gardens of RHS Rosemoor in Devon and Antony House in Cornwall. [S]

Documentary detailing the killer wave which struck the coast of the Bristol Channel in 1607. Two scientists are increasingly convinced that the wave was actually a tsunami. [S,AD]

Documentary. Jim Al-Khalili takes a look at how we've created machines that can simulate, augment, and even outperform the human mind - and why this shouldn't spook us. [S,AD,SL] [HD]

Programmes start at 7.00pm. [HD]

Programmes start at 7.00pm. [HD]

3/6. Fred Dibnah looks at how carpenters have used their talents to transform buildings such as Stokesey Castle, Little Moreton Hall and Harvington Hall. [S,AD]

9/10. Ben Robinson unearths the past of Greyabbey, a village on Northern Ireland's beautiful Strangford Lough, and discovers the history of its moneymaking kelp industry. [S] [HD]

1/2. Dan Snow and team take on the rapids of the Grand Canyon in antique wooden boats to rediscover one of the wild west's great adventures of discovery. [S,AD] [HD]

1/2. Amateur footage offers new insights into life in prewar Germany and during World War II. Contains some violence and disturbing scenes. [S] [HD]

Actor Spencer Banks reflects on his leading role in the 1974 Play for Today Penda's Fen. [S] [HD]

An awakened force in the landscape challenges a boy's clear and intense view of the world. Contains scenes which some viewers may find upsetting. [S]

1/2. Dan Snow and team take on the rapids of the Grand Canyon in antique wooden boats to rediscover one of the wild west's great adventures of discovery. [S,AD] [HD]

1/2. Amateur footage offers new insights into life in prewar Germany and during World War II. Contains some violence and disturbing scenes. [S] [HD]

3/6. Fred Dibnah looks at how carpenters have used their talents to transform buildings such as Stokesey Castle, Little Moreton Hall and Harvington Hall. [S,AD]

9/10. Ben Robinson unearths the past of Greyabbey, a village on Northern Ireland's beautiful Strangford Lough, and discovers the history of its moneymaking kelp industry. [S,SL] [HD]

Programmes start at 7.00pm. [HD]

Programmes start at 7.00pm. [HD]

4/6. Fred Dibnah travels to Scotland to demonstrate the engineering and design skills that shaped Scottish baronial style. [S,AD]

10/10. Ben Robinson discovers how the Scottish village of Johnshaven found wealth in cloth. [S] [HD]

What happened to a British ship and German U-boat that reportedly sank each other in 1917? [S,AD] [HD]

Classic western adventure, starring Paul Newman and Robert Redford as legendary outlaws Butch and Kid. [1969] [S,AD]

The career of Robert Redford is examined in this exploration of the BBC archives, which includes rarely seen interviews. Narrated by Sylvia Syms. [S]

The quiet English village of St Mary Mead is disrupted when a Hollywood film crew introduce inflated egos and cold-blooded murder. Miss Marple, of course, investigates. [1981] [S]

Friends, family and co-stars share their memories of the legendary Elizabeth Taylor. With Liza Minnelli, Joan Collins, Angela Lansbury and Sir David Frost. [S] [HD]

What happened to a British ship and German U-boat that reportedly sank each other in 1917? [S,AD] [HD]

10/10. Ben Robinson discovers how the Scottish village of Johnshaven found wealth in cloth. [S,SL] [HD]

Programmes start at 7.00pm. [HD]

Programmes start at 7.00pm. [HD]

Day 3 highlights from the third Test match between England and Pakistan at Edgbaston. [S] [HD]

Dvorak's epic, Britten's Young Person's Guide to the Orchestra and a new triple concerto for BBC Young Musician star alumni Sheku Kanneh-Mason, Jess Gillam and Ben Goldscheider. [S] [HD]

Peter Powell and Simon Bates present the pop chart programme, first broadcast on 13 August 1987 and featuring Def Leppard, Motley Crue, Rick Astley and The Jesus and Mary Chain. [S]

Gary Davies presents the pop chart programme, first broadcast on 13 September 1990 and featuring Sonia, Maria McKee and INXS. [S]

Documentary looking at the short but brilliant career of legendary rock 'n' roll star Buddy Holly. Features interviews with contemporaries and fans including Paul McCartney. [S]

The inspiration behind Buddy Holly's famous song provides fresh insights into his career. [S]

A celebration of rock 'n' roll in the shape of a compilation of classic artists and songs, featuring Jerry Lee Lewis, Dion, Dick Dale, Tom Petty, Joan Jett and Oasis. [S]

Peter Powell and Simon Bates present the pop chart programme, first broadcast on 13 August 1987 and featuring Def Leppard, Motley Crue, Rick Astley and The Jesus and Mary Chain. [S]

Gary Davies presents the pop chart programme, first broadcast on 13 September 1990 and featuring Sonia, Maria McKee and INXS. [S]

Documentary looking at the short but brilliant career of legendary rock 'n' roll star Buddy Holly. Features interviews with contemporaries and fans including Paul McCartney. [S]

Programmes start at 7.00pm. [HD]

Programmes start at 7.00pm. [HD]

Day 4 highlights from the third Test match between England and Pakistan at Edgbaston. [S] [HD]

Highlights from the second day of the 2026 Solheim Cup as Europe take on the United States, with the event being played in the Netherlands for the first time. [S] [HD]

A fatal gang shooting leads police to a mysterious figure with unknown motives. Contains strong language and prolonged violent scenes. [S] [HD]

6/8. Stately sitcom. Audrey waits for DeVere to go away before she herself goes on holiday. [S]

5/7. Sitcom. Hyacinth decides to have a second attempt at finding a small weekend home in the country, but she and Richard have different views on the word 'small'. [S]

1/7. Popular 1970s sitcom about a middle-class, middle-aged rebel. Why is Reggie referring to his mother-in-law as a hippopotamus? [S]

2/7. Reggie Perrin needs a month's holiday, but all he gets is an afternoon in a safari park with his wife, daughter, son-in-law and their two 'tiny adults'. [S]