The 'Gideon's Way' TV series was based on a series of novels by John Creasey. The series was written/published, under the pseudonym of J J Marrick, between 1955 ('Gideon's Day') and 1976 ('Gideon's Drive'). I picked up another Gideon novel at an op shop (thrift shop) which was written and published after after John Creasey's death but was written by someone else using the pseudonym J J Marrick (it was very poor).
As with the 60s TV series, 'The Baron', John Creasey is again strangely not credited here as at least the creator of the characters.