Benedict Cumberbatch flunked his maths exams.

The British actor is well known for playing supper smart detective Sherlock Holmes in the BBC TV series. But during his school days, Benedict didn't live up to his full potential.

"Way off," he laughed to the British edition of Hello! magazine when they asked if he was a great mathematician. "I got a B in GCSE maths [UK exams]. I was told I should have got an A, but I flunked it."

His lack of maths skills haven't had an impact on his latest acting role though, as he takes on real life code-cracker Alan Turing in The Imitation Game.

Co-starring Keira Knightley, the movie recounts the tale of how Alan helped to solve the Enigma code during World War II.

"I knew a little bit about him from the play Breaking the Code. And yet he's not in the front of history textbooks, as he should be. He's remarkably unknown in comparison to how important I think he is as a figure, politically as well as being a scientific figure," Benedict said.

While he was hailed a hero after the war, Alan's later life was more complicated. He was charged with gross indecency after admitting to a relationship with a man, an illegal act in the 1950s, and faced hormonal treatment designed to reduce libido. Two years later, he committed suicide.

"In recent years he has received a public apology from the Government and a posthumous pardon from the Queen for the way her was treated after the war.

"And it was a really cruel life that he suffered. But he never for one second played the victim, even to the point of making the suicide look like an accident to spare his mother's feelings," Benedict sighed.

"He never wanted to be a martyr, he never showed his suffering and I don't think he stood for a cause, but he was just true to himself, which is all anyone should ever have to be. That's why he is, in my mind, a true hero; a really true hero."

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