"He's the nicest, most professional, best actor" she gushes
Speaking at the film's star-studded premiere in London last night (October 22), the actress told BANG Showbiz: "I think Chris has chemistry with everyone he meets."
The brunette beauty, who plays scientist Jane Foster - Thor's love interest - in the film, continued: "He's the nicest, most professional, best actor."
Portman added: "He's very easy to be around. It's definitely not something we needed to work at and I think that says so much about him. He's a great guy."
The 32-year-old actress looked stunning in a metallic silver skirt and simple black top at the big event, which she attended with her husband, professional ballet dancer Benjamin Millepied.
The star also told reporters about a scene in the film where she gets to slap Hemsworth, calling the moment "very satisfying".
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