Sink or Swim is a BBC TV sitcom starring Peter Davison as Brian Webber, who lives in a flat above a London petrol station, and trying to make his way in the world, thus far with limited success. His girlfriend, Sonia, is a very practical young woman who is passionate only about things like vegetarianism and ecology. When Brian's younger brother, Steve, arrives seeking a place to stay, his lazy, cynical, noisy "Northern lout" attitude disrupts Brian's already messy life.

Like Only Fools and Horses, Sink or Swim was filmed in Bristol doubling for London. It ran for three series between 4 December 1980 and 14 October 1982, and was written by Alex Shearer, who later wrote the Nicholas Lyndhurst sitcom 'The Two of Us' (1986-90, LWT). The first two years of production overlapped as Davison was also starring as the Fifth Doctor in Doctor Who, which imposed constraints on recording schedules.