In 1939, when World War II broke out, Lee volunteered to fight with the Finns. But he and other British volunteers were kept away from fighting, mostly serving on guard duty, well away from the front lines, so that didn't last long. In 1941, Lee volunteered for the Royal Air Force.
Lee reported to the RAF for training and then was posted to a number of training posts, but suffered from headaches and blurred vision just before his first solo flight.. A failure of the optic nerve was diagnosed, and he was told he would never be allowed to fly again.
He joined RAF Intelligence. His wartime career, as his Hollywood career, was varied and, at times, deadly. He was nearly blown up at least twice, once by an enemy bomb, once by one of our own. He came down with malaria six times in a single year. Lee retired from the RAF in 1946 with the rank of flight lieutenant.
Lee has mentioned that during the war he was attached to the Special Operations Executive and the Long Range Desert
"I was attached to the SAS from time to time but we are forbidden – former, present, or future – to discuss any specific operations. Let's just say I was in Special Forces and leave it at that. People can read in to that what they like"
Sir Christopher Lee is 92. Sir, we thank you for your service.
Update: Mr. Lee passed away June 11, 2015. RIP, Mr. Lee