William Nicholson Simpson (11 September 1931 – 21 December 1986) was a Scottish actor, best remembered for his portrayal of the title role in the long-running BBC TV series Dr. Finlay's Casebook.

[1][2] His only appearance in a movie was as a non-speaking extra (his name was missing from the film credits) playing a bridegroom in the first remake of John Buchan's story The 39 Steps (1959), which starred Kenneth More as Richard Hannay.

[5] On 16 August 1962 the BBC began broadcasting its long-running Scottish medical drama Dr Finlay's Casebook, with an episode called "It's All in the Mind".

He played Sir Andrew Kilbrane, alongside Michael Jayston as Quiller, in an episode called "Target North", which involved the death of a government minister.

[10] Simpson had a feature part in "Happy New Year, Some Say", a 1976 episode of the North East England drama When the Boat Comes In, playing Sandy Lewis.

[18] Later that year, he appeared as Dr. Hugh McFarlane in the Yorkshire Television series The Good Companions, a "very unusual musical comedy drama" based on the novel by J.

He contributed less to television drama, and more to factual subjects, introducing the TV coverage of the British Open Golf Championship at Royal Troon in 1982, with Peter Alliss,[20] and presenting "Leadership Matters", a middle management corporate video on behalf of The Industrial Society in 1984.

[26] On 24 July 1965 Simpson married the actress Mary Miller in Callander, near Menteith, Scotland and the couple bought a house there, called Tamavoid.