The Tunnel (7.40pm BBC2) The Channel Tunnel was a project envisaged as long ago as the reign of Napoleon, but it took another powerful leader, Margaret Thatcher, to make it finally happen many years later. This new three-part series retraces the history of the tunnel - the first part, narrated by James Naughtie, follows the unusual negotiations between the free-marketeer Mrs Thatcher and the Socialist President of France, Francois Mitterand, which led to the agreement to construct the link.

Cancer Wars (8pm C4) Cancer can be seen as the dominant illness of the late 20th century. One person in three suffers from it, and trillions of dollars are spent in pursuit of a cure for it. This new four-parter recounts the history of the disease. It opens with "Blind Eye to Danger", which demonstrates how early warnings about the illness were ignored.