William Watt is an ordinary businessman, a social climber, a fool. The local community is convinced that he has murdered his family. Peter Manuel is a famous liar, a rapist, a criminal. He claims he can get hold of the gun that was used. Watt is desperate to prove his innocence. One December night in 1957, he meets Manuel in a Glasgow bar to find out what he knows ... Based on the true story of a 1950s Glasgow murder mystery.