Before he appeared as The Creature in Curse of Frankenstein, Christopher Lee received some acting advice from Boris Karloff
Karloff was able to share some monstrous wisdom.

Despite his frequent appearances in frightening films, Christopher Lee had an unorthodox approach to the horror genre.
During an interview, Lee stated that he believed that a truly remarkable horror film offered the audience an escape from the woes of the real world. Lee seemed to remain steadfast in a “less is more” philosophy.
“There is too much real horror in the world for us to need to re-enact it on screen,” said Lee during an interview with the Evening Chronicle. “I believe it is my job to make the unbelievable believable, and I think this can be done in the main by subtlety and suggestion, although too often producers do insist on unnecessary amounts of blood and gore.”
Lee wasn’t alone in this philosophy. As the actor was preparing to take on the role of The Creature in the 1957 film, The Curse of Frankenstein, he was afforded a rare gift: A piece of advice from the Monster himself, Boris Karloff.
Karloff had played the Monster in Universal's Frankenstein (1931). Lee and Karloff became friends, and Karloff even offered the actor some guidance on how to approach the more horrific elements of his portrayal.
“You must leave it to the imagination because of the audience,” Karloff told Lee. “Because whatever you or I or anybody else ever does, they will surely think of something far more terrifying.”