text: He appeared in In This House of Brede (1975) with Diana Rigg and played Alan in the 1976 version of The Picture of Dorian Gray, alongside Peter Firth. Clay was in Terror of Frankenstein (1977) then did Saturday Sunday Monday (1978) with Laurence Olivier.
  In 1978 he played Henry Wriothesley, 3rd Earl of Southampton in the drama series Will Shakespeare, about the life of Shakespeare.
  Clay had a small role in Zulu Dawn (1979) and was in Lovespell, filmed in 1979 but not released until 1981. He played Orestes in The Greeks: A Journey in Space and Time (1980).
  In 1981 he gave his most widely seen screen performance, as Lancelot in the 1981 film Excalibur.  He followed it playing the title role in The Search for Alexander the Great (1981). He appeared in Just Jaeckin's film version of D.H. Lawrence's Lady Chatterley's Lover (1981), playing Mellors, and in Agatha Christie's Evil Under the Sun (1982), the latter reuniting him with Diana Rigg, his co-star in The Misanthrope. Director of Evil Guy Hamilton said "I was looking for someone like Stewart Granger or Michael Rennie - handsome, dashing, physical, romantic. Nick has it all. A fine sense of timing, the right looks and a good physique."
  For TV Clay was in The Agatha Christie Hour (1982), in an adaptation of "In a Glass Darkly" then Russian Night... 1941 (1983), The Hound of the Baskervilles (1983) and The Last Days of Pompeii (1984).