The Horse's Mouth is a 1958 film directed by Ronald Neame. Alec Guinness wrote the screenplay from the 1944 novel The Horse's Mouth by Joyce Cary, and also played the lead role of Gulley Jimson, a London artist.
The film begins with the release of the eccentric painter Gulley Jimson (Alec Guinness) from a one-month jail sentence for telephone harassment of his sponsor, Mr Hickson (Ernest Thesiger). Nosey Barbon (Mike Morgan), who wants to be a protégé of Jimson, greets Jimson at Wormwood Scrubs, but Jimson tries to discourage Nosey from pursuing painting for a living. Jimson makes off with Nosey's bike to make his way back to his houseboat, which Coker, an older lady friend, has been attending in Jimson's absence...oh just watch the bloody movie if you want to know what happens!