Adam Strange, a retired Home Office criminologist, solves bizarre cases – which had been marked "Open File" by various government departments – with the help of Hamlyn Gynt (Kaz Garas), Evelyn (Anneke Wills) and Professor Marks (Charles Lloyd-Pack). He employed the latest techniques in forensic investigation, which he undertook in his own laboratory in his flat in Warwick Crescent in the Maida Vale/Little Venice area of Paddington.