In 1840s London, Dr. Thomas Bolton [Boris Karloff] dares to dream the unthinkable: experimenting with anesthesia gases to make surgery pain-free. While doing so, his demonstration before a panel of his peers ends in a horrific mishap with his patient awakening under the knife; he is forced to leave his position in disgrace. To complicate matters, he becomes addicted to his own chemical experiments and gets involved with a criminal gang led by Black Ben [Francis de Wolff], and a ruthless killer Resurrection Joe [Christopher Lee]. Unfortunately, this shady partnership leads Dr. Bolton to further ruin, culminating in his unwitting participation in murder — for which he becomes the first victim of a blackmail scheme.
Boris Karloff
Betta St. John
Christopher Lee
Finlay Currie
Adrienne Corri
Francis de Wolff
Francis Matthews
Frank Pettingell
Basil Dignam
Nigel Green
Yvonne Romain
Howard Lang
Charles Lloyd Pack
Bernard Archard
Marianne Stone
Desmond Llewelyn
Skip Martin