TV Guide BBC Four Wednesday

Michael Portillo continues his post-war exploration of northwest England in Bradford, Shipley and Hebden Bridge. In Bradford's Centenary Square, he encounters local literary giant, JB Priestley. At Shipley station, Michael discovers a nature reserve in the middle of the car park. Finally the Calder Valley Line delivers the presenter to the photogenic station at Hebden Bridge

Julia Bradbury explores the 2,500ft summit of High Street in the Lake District's fells, used as a path 2,000 years ago by the marching Roman legions. She then descends into the mysterious valley of Mardale, where the local village was lost when the Haweswater reservoir was created

The physicist reflects on the most challenging and intriguing questions facing science today, using material from his past programmes and the latest scientific research. He begins by looking at how far the exploration of the cosmos can go, believing that humanity is at the start of a new age of travel where space flight is on the verge of becoming routine

Explorer Bruce Parry travels to some of the world's most remote areas to live with indigenous tribes. In this show he travels to the Amazon rainforest to meet the Matis people, whose first contact with westerners did not come until the 1970s. Still living the traditional way of life, hunting pigs, stalking monkeys and participating in rituals, they have now embraced football and will soon host their first disco

Smiley plans to visit old friends after discovering Vladimir quarrelled with his postman Toby Esterhase. Dramatisation of John le Carré's spy novel, starring Alec Guinness, First broadcast in 1982

The agent gets into trouble with his superiors, who want the investigation closed. However, Smiley encounters the woman he wishes to speak with and gets her account. Dramatisation of John le Carré's spy novel, starring Alec Guinness

The broadcaster explores the conventions of the fantasy genre, profiling key figures including JRR Tolkien, CS Lewis and Terry Pratchett and chatting to best-selling writers Neil Gaiman, Alan Garner and Frances Hardinge