Alone Radio 4, 6.30pm

Angus Deayton (right) and Abigail Cruttenden return for the fourth run of the comedy about middleaged neighbours in North London. Mitch and Ellie’s relationship continues to cause ripples, while their friend Morris simply wants someone to cook him a Sunday roast.

A six-part series of The Curious Cases Of Rutherford & Fry (Radio 4, 11am) begins with an investigation into why some things immediately catch the eye or ear, while others are ignored.

Anne McElvoy hosts a new threeepisode run of Across The Red Line (Radio 4, 9am), in which people with opposing political views are invited to discuss and explain their position.