David Suchet

Sir David Suchet (born 2 May 1946 ) played the Landlord in the Doctor Who television story Knock Knock.

Outside of Doctor Who, Suchet is best known for his role as the famous Belgian detective Hercule Poirot in the ITV series Agatha Christie's Poirot, which was adapted from the works of Christie herself. He played the role between 1989 and 2013.

He also played composer Antonio Salieri in the 1999 Broadway play Amadeus, alongside Michael Sheen's Mozart. Suchet personally won two awards for this role.

Speaking on ITV's Lorraine, Suchet revealed that he took the job without first reading the script. "When my agent rang up and said they'd like you to be in Doctor Who, I said, 'Yes'. She said, 'Do you want to read the script first?' I said, 'No, I just want to be in one'."