Denis Lill is a New Zealand-born British actor.
Denis Lill joined the RNZAF as a 13 course BES cadet entrant in 1959. It was in the RNZAF that he first expressed an interest in amateur dramatics, and a fondness for mimicking characters of the BBC's "The Goon Show". Throughout his air force career, he involved himself in operatic and theatric productions.
Some of his many film and television roles include Fall of Eagles, Edward the Seventh, Survivors, The Scarlet Pimpernel, as William Knox D'Arcy, the Australian oil pioneer in Persia, in Reilly: Ace of Spies, Rumpole of the Bailey, Mapp & Lucia, Only Fools and Horses, Richard III, Evita, and Rebecca.
Lill twice appeared in the BBC's science fiction series Doctor Who: as Dr Fendelman in the 1977 serial Image of the Fendahl and as Sir George Hutchinson in 1984's The Awakening. After a one-off appearance in the first series of Terry Nation's post-apocalyptic drama Survivors as Charles Vaughan, he became the leading actor for the show's second and third series. In the 1990s he starred in sitcoms Outside Edge as Dennis and Only Fools and Horses as Alan Parry.