New series 1/8. With the London Marathon mere weeks away, 13 novice runners from around the UK volunteer to train for the gruelling 26.2-mile event. But not only are the group unfit, many are also battling personal traumas, from cancer to disabling road accidents. Sally Gunnell and Steve Cram are their tough coaches and tonight put the would-be entrants through a gut-wrenching high-ropes course. Producer Ian Holt ; Executive producer Annette Clarke