BBC Four Wednesday

Michael Portillo continues his post-war exploration of northwest England in Bradford and Shipley, before ending this leg of his journey at Hebden Bridge

Julia Bradbury retraces the steps taken by Roman legions on the summit of High Street in the Lake District's fells, and visits the valley of Mardale

The physicist reflects on the most challenging and intriguing questions facing science today, beginning by looking at the limits of human exploration of the universe

Bruce Parry travels to the Amazon rainforest, where he stays with the remote Matis people, whose first contact with Westerners did not come until the 1970s

Smiley plans to visit old friends after discovering Vladimir quarrelled with his postman Toby Esterhase. Alec Guinness stars

The spy 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

The broadcaster explores the fantasy genre, profiling key figures including JRR Tolkien, CS Lewis and Terry Pratchett. With Neil Gaiman, Alan Garner and Frances Hardinge

Michael Portillo continues his post-war exploration of northwest England in Bradford and Shipley, before ending this leg of his journey at Hebden Bridge

Julia Bradbury retraces the steps taken by Roman legions on the summit of High Street in the Lake District's fells, and visits the valley of Mardale

Bruce Parry travels to the Amazon rainforest, where he stays with the remote Matis people, whose first contact with Westerners did not come until the 1970s

The physicist reflects on the most challenging and intriguing questions facing science today, beginning by looking at the limits of human exploration of the universe