GRAHAM SATCHWELL served in every rank of CID within the British Transport Police (1978-1999). For many years Britain's most senior railway detective, his books include, 'Great Train Robbery Confidential' and 'An Inspector Recalls' for The History Press. WINSTON TREW was wrongly convicted of theft and assault as one of the Oval Four in 1972. His conviction was finally overturned in December 2019. He has previously published a personal memoir, Black for a Cause.