The Man Upstairs (1958)

Charles Houston plays artist Nicholas

The Man Upstairs on IMDB

 Nicholas the artist rushes to answer the door to the police while his model hastily pulls on her clothes in his bed

Nicholas' model Eunice persuades him to answer the door to the police again and find out what is going on

Nicholas and his Model Miss Blair join the other residents of the house downstairs, while the police deal with the disturbed man upstairs

Peter Watson is troubled with pain and an inability to sleep. He tries to light the gas-fire and seeks help from another lodger, artist Nicholas, who is spending the night with his model, and is reluctant to be disturbed. Another neighbour, Pollen calls for police help. The others in the boarding house are awaken by this time, and Mrs. Harris tries to help the mentally confused Watson but he also refuses her help. The police clash with Dr. Sanderson, a welfare worker, who thinks he can take the gun-toting Watson without complications, but when a police sergeant is injured, Police Inspector Thompson is determined to take Watson by force if necessary.
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