Turns out there was more than butterbeer in Daniel's Radcliffe's system on the Harry Potter sets.

"I have a very addictive personality. It was a problem," the Brit told U.K.'s Heat magazine earlier this week concerning his former struggling with an alcohol addiction. "People with problems like that are very adept at hiding it. It was bad. I don't want to go into details, but I drank a lot and it was daily -- I mean nightly."

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But the actor, who starred in the eight Harry Potter franchise films from 2001 to 2011 beginning at the age of 11, insists that like any good Gryffindor house member, he didn't bring his indiscretions to class, er, work.

"I can honestly say I never drank at work on Harry Potter," Radcliffe, 22, adds. "I went into work still drunk, but I never drank at work. I can point to many scenes where I'm just gone. Dead behind the eyes."

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The star, whose new movie The Woman in Black hits theaters Friday, came clean about his vices in a July interview with U.K. GQ magazine.

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"I became so reliant on alcohol to enjoy stuff," he said to the men's mag. "There were a few years there when I was just so enamored with the idea of living some sort of famous person's lifestyle that really isn't suited to me."

Radcliffe also added that he has been clean and sober since 2010.

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