TV tonight: the extraordinary story of the 1994 murder that shocked Orkney

The Man in the Mask: An Orkney Murder 9pm, BBC TwoIn 1994, 26-year-old Shamsuddin Mahmood was shot dead as he served food in an Indian restaurant in Orkney. Fourteen years later, teenager Michael Ross was found guilty of the murder. Ross still denies it, and he speaks from prison in this true-crime series. As journalist Hazel Martin re-evaluates events, she also talks to Mahmood’s family, Ross’s mother and some of those who worked on the shocking case. Hollie Richardson Celebrity Race Across the World 8pm, BBC One The backpacking dash down the Pacific coast of Central America reaches its halfway point. Our four likable duos must navigate their way through Costa Rica to reach Panama. Highlights include DJ Tyler West’s OTT collection of LED torches and Roman Kemp’s hair going “a bit Ace Ventura”. Graeme Virtue Cancer Detectives: Finding the Cures 9pm, Channel 4Narrated by Lenny Henry, this eye-opening series profiles those at the cutting edge of cancer research. For Cambridge neurosurgeon Richard Mair, speed is the key to tackling insidious brain cancers; optimising the analysis of tumour DNA means effective drugs can be given as soon as possible to those taking part in his trials. GV The Death of Bunny Munro 9pm, Sky AtlanticMatt Smith’s increasingly unbearable antihero Bunny Munro is haunted by his wife’s suicide, as he continues his version of looking after their young son in this adaptation of Nick Cave’s contentious novel. That involves making Bunny Jr wait in the car while he woos women with his makeup products. HR The Ridge 9.45pm, BBC Two Despite (or perhaps because of) ripping through a close-knit community in New Zealand like an opioid-addicted hurricane, sweary Scottish medic Mia (Lauren Lyle) is getting closer to the truth about her sister’s lethal climbing accident. But by churning up local secrets, is she alienating everyone who could help her? GV Australian Survivor 10.10pm, BBC ThreeThe hit Aussie take on the survival show reaches its ninth series – and in the wilderness of Charters Towers, Queensland, it’s as action-packed as ever. The opening double bill introduces us to the 12 pairs of contestants, before the first tribe vote sends someone packing. HR