Manchester native David Warner supported himself as a book salesman while studying at the Royal Academy of Dramatic Arts. Warner made his stage bow at the Royal Court Theater in 1962, the same year that he first appeared on television. In 1965, Warner became the youngest-ever member of the Royal Shakespeare Company to tackle the role of Hamlet. In films from 1963 (he played Master Blifil in Tom Jones), Warner achieved international fame for his star turn as the certifiably insane protagonist of Morgan! (1966). His appearance as the village idiot in Straw Dogs (1971) went uncredited due to an injury that rendered him uninsurable on the set; but this was the only time that Warner's contribution to a film would ever go unofficially unheralded. Seldom settling for a normal, sedate characterization, Warner has been seen as Jack the Ripper in Time After Time (1981), the Evil Genius in Time Bandits (1983), Dr. Alfred Necessiter (who had some interior decorator!) in The Man With Two Brains (1984), and genially eccentric Professor Jordan Perry (a good guy, for a change) in Teenage Mutant Ninja Turtles 2 (1992). He has also played two different roles in two consecutive Star Trek films. On television, David Warner has played Heydrich in Holocaust (1978), Pomponius Falco (a performance that won him an Emmy) in Masada (1981), and Bob Cratchit (what-not Scrooge?) in the 1984 adaptation of A Christmas Carol.
- Worked as a bookseller before discovering his passion for acting.
- Made his professional stage debut as Snout in the English Stage Company's production of A Midsummer Night's Dream in 1962.
- Joined the Royal Shakespeare Company in 1963, portraying Trinculo in The Tempest, Cinna the Poet in Julius Caesar, the titular role in Hamlet and Henry VI in multiple productions.
- Returned to the stage in 2002 after 30 years to star in Olaf Olafsson's production of The Feast of the Snails at the Lyric Shaftesbury in the West End after long suffering from acute stage fright.
- Played the titular role in Steven Pimlott's stage production of King Lear at the Chichester Festival Theatre in 2005.
- Has done extensive voice-over work for numerous TV series, video games, audio plays and radio productions.
- Accrued more than 200 on-screen acting credits throughout his career.