The owner of a coal mining operation, falsely imprisoned for fratricide, takes a drug to make him invisible, despite its side effect: gradual madness.
Framed for the murder of his brother, Geoffrey Radcliffe is scheduled to hang. After a visit from his friend Dr. Frank Griffin, he vanishes mysteriously from prison. Police inspector Sampson realizes that Griffin is the brother of the original Invisible Man and has given Geoffrey the formula to aid his escape. Can Geoffrey elude the police dragnet and track down the real murderer? More importantly, can Griffin discover an antidote before the invisibility formula drives Geoffrey insane?—P. Silvestro
Geoffrey Radcliffe, the wealthy owner of a coal mining operation, is running out of time. In two hours, he is set to be executed for the murder of his brother, a murder he did not commit. His fiancée, Helen Manson, is frantic. Geoffrey's cousin, Richard Cobb, tells her that he has done everything he can. Geoffrey's only hope is his friend, Dr. Frank Griffin. Griffin's late brother once discovered a secret drug that makes a human being invisible. The only trouble is, it also turns its subject mad. But now Geoffrey, Helen and Dr. Griffin have no other choice. Griffin visits Geoffrey at the prison and administers the drug. Soon Geoffrey, made invisible, is able to escape. As the wily Inspector Sampson of Scotland Yard searches for the escaped convict, Griffin frantically searches for an antidote and Geoffrey frantically searches for the real killer. Time is short. Geoffrey is slowly but surely going insane.—J. Spurlin
Framed and convicted for murder Geoffrey Radcliffe (Vincent Price) believes that the real culprit is someone closely associated with the colliery where the murder was committed. Radcliffe convinces his friend Doctor Frank Griffin (John Sutton) to inject him with the invisibility serum that his father Jack Griffin had created. Griffin does so but warns Radcliffe that the earlier invisible man went insane under the drug. Once he is invisible Radcliffe goes to his fiancée Helen Manson (Nan Grey) to assure her of his intentions and the young woman notices the changes taking place in his demeanor. Radcliffe uncovers the truth by kidnapping Richard Cobb (Cedric Hardwicke) and in a final confrontation and shootout with the police the truth comes out but at a high cost to everyone.
