A mixed party of West Indian settlers arrives in London, where they encounter prejudice from the white population and integrate themselves into the existing West Indian community.
While perusing the books of an engineering company, fastidious auditor Frank Manning encounters rum goings on when he is approached by a woman who claiming she is being blackmailed. She begs him to find certain letters and he eventually agrees. Having obtained the letters, he takes them to a specified address where, to his horror, he finds a man, fully clothed, dead in the bath.
James Stewart plays aeronautical engineer Theodore Honey, the quintessential absent-minded professor: eccentric, forgetful, but brilliant. His studies show that the aircraft being manufactured by his employer has a subtle but deadly design flaw that manifests itself only after the aircraft has flown a certain number of hours. En route to a crash site to prove his theory, Honey discovers that he is aboard a plane rapidly approaching his predicted deadline.
