But after playing a second mute in The Old Dark House Karloff was dismayed to learn that this time around he would only be seen for a few seconds at the end (though the character's appearance throughout the film, in bandages, dark glasses and false nose, became iconic in its own right). but never seen until a brief climactic close-up, and declined the role at a relatively late stage. Consequently, Whale was able to give another Englishman his big break, thus beginning Claude Rains on a long career that only occasionally overlapped with the horror genre.
Of all Whale’s horror films, even the blatantly weird Bride of Frankenstein, this is the one that bothers least with generic suspense and horror sequences and plunges most overtly into black comedy, helping disguise the fact that Rains’s Dr Griffin is the most brazenly evil of all his protagonists, with only chemically-induced insanity to excuse his gloatingly sadistic behaviour. Even modern audiences may be taken aback by the glee with which he stages a train wreck, proposes to hold governments to ransom, enslave the world, “rob, rape and kill,” and brags about cracking open the skull of a policeman, apparently solely for the crime of being stupid.
Whale’s keen eye for telling images and odd juxtapositions, seen in such celebrated images as the mysterious scientist Dr Griffin unravelling the bandages around his head to reveal only empty space beneath, a terrified man being swung around by unseen hands, and a pair of trousers chasing a screaming woman down a country lane, created a sensation and have since entered movie legend. (The invisibility effects were achieved via a complicated matte process that required Rains to wear a tight-fitting black velvet body covering and then filming him against a black background, so that when combined with film of the location only his clothes were visible.)
The plot, though based more closely on H.G. Wells’s original novel than might be supposed (especially considering some of the original treatments inherited by R.C. Sherriff, the English writer and friend of Whale’s hired to make sense of them, one of which revealed him as a Martian), also adheres strongly to the Frankenstein model, with Griffin as combined Frankenstein and Creature, meddling in things best left alone and paying the price, and featuring the same supporting triumvirate of father figure, disapproving colleague and beautiful blonde love interest, the latter the charming Gloria Stuart, late of Whale’s Old Dark House. (Universal tended to play safe in this way once a hit formula had been established: it will be noted that The Mummy  is to all intents a restaging of Dracula .) A huge hit, the film spawned a more than usually eccentric run of sequels, in which a succession of invisible men (and one woman) were, in sequence, innocent good guys, comic leads, war heroes and, finally (in The Invisible Man’s Revenge, the best of the bunch from 1944), ranting and evil once again.
It is often claimed that the film errs in showing shoeprints, rather than footprints, as the naked Griffin flees his pursuers through the snow, but the tracks are indefinite and could surely be either.