In 19th century England, a noted brain surgeon rescues a former student from being hanged on a false conviction for murder, and spirits him away to an ancient, repurposed abbey far in the countryside. There, he connives his pupil into assisting him in mapping the functions of the various parts of the human brain, using living subjects who are under a terrible animation-suspending drug called "black sleep". Subsequently, the student, along with the daughter of one of the subjects, discover that most of these subjects have survived but are being kept in a dungeon-like cellar, in various stages of physical and mental derangement...

A Royal navy Commander is tricked by a pretty girl who is working for the Nazis. She tricks him into revealing some military secrets and he is court martial. He vows to track her and her accomplices down.

A young boxer falls in with a crooked fight promoter.

Sister Mary presides over a convent where a convicted murderess, who is being escorted to Death Row, is stranded by bad weather. She is slowly becoming convinced that Valerie is innocent so Sister Mary sets about to clear the girl and bring the real killer to justice.

Variety performances by acts including the Albert Sandler Quartet, Betty Astell, Reggie Bristow's Band, the Modernique Quartette, Stanelli and Edgar, Terence McGovern's Band and Trio, the Nile Players, Phyllis Stanley, and Arthur Travers.

A former housemaid teams up with an English gentleman thief and works a confidence game to bilk the wealthy but their plans for a big job in California go awry.

Romance in Rio for a girl of the embassy staff.

Saloon entertainer Vermilion O'Toole and her former partner in crime Newt Cole escape from a train ride to prison and hide out in logging town Timberline. Meanwhile, the three sons of widower Will Hall come to town in search of a wife for their dad. Vermilion needs to lay low to escape the marshal, so she accepts the boys' offer to visit pioneer community Pine Grove. Once there, she annoys local Mrs. Grundys but eventually starts to fit in.

Lots of slogans such as "Be like Dad, Keep Mum" and "Keep it under your Hat" are visible on the walls in various scenes to reinforce the plot of this British wartime movie illustrating how gossipy talk can result in unknowingly giving valuable information to Nazi spies.

A young poultry farmer is flattered and persuaded into financing a film production. He attempts to interfere in the direction, is swindled and left in the lurch but eventually manages to turn the tables on his former associates.