Actor Benedict Cumberbatch says playing genius detective Sherlock Holmes in TV series 'Sherlock' made his brain hurt.

Cumberbatch, 35, said delivering the sleuth's dazzling, lightning-fast speeches of deduction was more exhausting than any other role he has taken on, Daily Sun reported. "Every deduction is hard.

It's always a painful process. There are all the details. It's like a stream of consciousness of incredibly condensed information.

"He just goes at 100 miles an hour and it's a huge speed to rush it out. It's just hard, it's hard graft there's no other word for it," he said. He also praised his co-star Martin Freeman, who plays Holmes' sidekick Watson.

"I'm not saying Martin has an easy job because what he does is with scalpel precision and he works incredibly hard. "But he has a photographic memory, he looks at the lines in the morning and it's learned, that's it," he added.

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