What did Andy Serkis base Gollum’s voice on for the Lord of the Rings movies?

Go ahead, you know want to — say "my precious" in your best Gollum voice.

Andy Serkis rules. Whether he's acting as a cursed hobbit in a motion capture suit, stealing vibranium, or engineering an escape from an Imperial prison, if he's in something you're watching, you know it's going to be good.

Serkis turned in one of the great voice-acting performances in film history with Gollum/Smigel from the Peter Jackson Lord of the Rings movies. But what did he base that voice on?

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