The Professionals, which made stars of Lewis Collins and Martin Shaw, was based around the adventures of a fictional crime fighting unit called CI5.
Its memorable theme tune and action-packed plots made it a huge hit on ITV in the late 1970s and early 1980s.
Collins's other most notable role came in 1982's Who Dares Wins, when he played a member of the SAS.
He was born on Merseyside and worked as a drummer in local bands and as a hairdresser before getting into acting.
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