This is quite a good, if a little preposterous sequel. Vincent Price - or, that is, his voice - owns a successful mining business who is framed for killing his brother. With but two hours to go before he goes to the gallows, he turns to his friend who has devised a secret drug that can render the user invisible - but at a cost: continued exposure leads to madness. Once he has used the drug to escape from prison, he attempts to track down the real culprits from his close confederates - including Sir Cedric Hardwicke, John Sutton and a glamorous Nan Grey. The ever vigilant "Inspector Sampson" (an on-form Cecil Kellaway) is also on the trail of the transparent fugitive and all in all, we have a decently paced mystery thriller with some quite fun dialogue and special effects that bely that fact that this was made at the very start of WWII with not much of a budget.