Speaking in the latest issue of Empire, the actor - who played Chancellor Valorum - said he initially didn't want the part but was persuaded by his agent and his admiration of an up-and-coming young actress.
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"I came all the way back from Australia to do it," Stamp said. "I didn't want to but my agent leaned on me and I wanted to meet Natalie Portman because I'd seen her in 'The Professional' [aka 'Léon']. And I did meet her and she was absolutely enchanting."
However disappointment was to follow, "On the day I'm supposed to do my scene with her, for which I'd travelled halfway around the world, I say, 'Where's Natalie?' And George [Lucas] says, 'That's Natalie,' and points at a bit of paper on the wall. It was just boring."Stamp also spoke about his brief time with George Lucas, and what he thought of the 'Star Wars' creator.
"We didn't get on at all. I didn't feel like he was a director of actors; he was more interested in stuff and effects. He didn't interest me and I wouldn't think I interested him."
The full career-spanning interview can be found in the March issue of Empire.