Paul Gregory (William Sylvester aka: Dr. Heywood R. Floyd in 2001: A Space Odyssey) is an accomplished composer despite his blindness and beautiful Anne (Barbara Shelley) seems to be the perfect supporting wife. But unknown to Paul, she is having a passionate affair with Ricky (Alexander Davion), a struggling artist. Keen to support her artist lover and give them more time to make love, she persuades Paul to commission Ricky to paint her portrait. But Paul senses their affection for each other and threatens to cut Anne off without a penny. Desperate to keep both her lover and Paul’s money, Anne plots the perfect murder and asks Ricky to carry it out.