BBC Four HD

Programmes start at 7.00pm.

Series exploring the paradise of Thailand. Northern Thailand, dominated by mountains and forests, hides ancient creatures and surprising partnerships.

A journey into the eye-opening realm of insects to explore how scientists are using traditional and cutting-edge techniques to search for a single, common insect ancestor.

Documentary which follows the construction of a trailblazing 36,000-tonne steel structure to entomb the ruins of the nuclear power plant destroyed in the 1986 Chernobyl disaster.

In his search for the mole sitting at the heart of the Circus, Smiley sets out for Oxford to visit an invaluable friend.

Smiley recalls the past and his involvement with Tinker, Tailor, Soldier and Poorman, and Karla - the legendary head of Moscow Circus.

Smiley thinks that the time has come to call on Jim Prideaux, whose assignment to Czechoslovakia went disastrously wrong, with the mole at the heart of the Circus to blame.

A journey into the eye-opening realm of insects to explore how scientists are using traditional and cutting-edge techniques to search for a single, common insect ancestor.

Documentary which follows the construction of a trailblazing 36,000-tonne steel structure to entomb the ruins of the nuclear power plant destroyed in the 1986 Chernobyl disaster.

Series exploring the paradise of Thailand. Northern Thailand, dominated by mountains and forests, hides ancient creatures and surprising partnerships.

Programmes start at 7.00pm.

Programmes start at 7.00pm.

Paul Rose explores the 79 miles of the Yorkshire Wolds Way, arguably Britain's least well-known national walking trail, starting at the Humber Estuary and ending at Filey.

Archaeologist Ben Robinson explores the rise, fall and rise of Lavenham in Suffolk, the best-preserved medieval village in the country.

A group of crack commandos during the Second World War attempt to destroy the formidable German artillery on the Greek island of Navarone. Starring Gregory Peck and David Niven.

World War II action about a German plot to kidnap Winston Churchill. With Michael Caine. Contains some violent scenes.