Thomas Nigel Kneale (28 April 1922 – 29 October 2006) was a Manx screenwriter who wrote professionally for more than 50 years, was a winner of the Somerset Maugham Award, and was twice nominated for the BAFTA Award for Best British Screenplay.

Predominantly a writer of thrillers that used science-fiction and horror elements, he was best known for the creation of the character Professor Bernard Quatermass. Quatermass was an heroic scientist who appeared in various television, film and radio productions written by Kneale for the BBC, Hammer Film Productions and Thames Television between 1953 and 1996. Kneale wrote original scripts and successfully adapted works by writers such as George Orwell, John Osborne, H. G. Wells and Susan Hill.

He was most active in television, joining BBC Television in 1951; his final script was transmitted on ITV in 1997. Kneale wrote well-received television dramas such as The Year of the Sex Olympics (1968) and The Stone Tape (1972) in addition to the Quatermass serials. He has been described as "one of the most influential writers of the 20th century", and as "having invented popular TV".