Cast members Michael Fassbender attends a news conference for the film Fish Tank by Director Andrea Arnold at the 62nd Cannes Film Festival May 14, 2009. REUTERS/Regis Duvignau

He may not be a household name in the United States, but Michael Fassbender is fast becoming one of the hottest young stars in Hollywood.

The actor got his big break when Steven Spielberg and Tom Hanks cast him in their Band of Brothers World War Two mini-series. He also appeared in the hit movie 300.

In August, Fassbender drew acclaim for his portrayal of undercover British military man Archie Hicox in Quentin Tarantino's Inglourious Basterds.

He is also winning praise low-budget Fish Tank, a coming-of-age tale in which he plays a handsome young man who strikes up a volatile relationship with frustrated teenager played by newcomer Katie Jarvis.

The movie won the Jury Prize at the Cannes film festival, and has been for eight British Independent Film Awards. It will not be shown in the United States until January.

Fassbender spoke to Reuters about the film, swimming with sharks and fighting with actress Megan Fox.

Q: There's a lot of sexual tension in Fish Tank.

A: Yeah, absolutely. It's about this 15-year-old girl coming to terms with her sexuality and where she is in her life -- growing up in a council estate, which would be like the projects in America, and feeling that she can never escape. Then I appear and I'm a catalyst that provokes her to get out and do something. Regardless of the questionable things Connor does, he gives her a confidence and self-belief that her own mother isn't capable of giving.

Q: Is it true that director Andrea Arnold cast you without meeting you, even though she'd planned to cast a non-actor?

A: Yes, she'd seen me in Wedding Bells, a BBC show, and thought I'd be perfect for Connor. I got a call telling me she wanted me, and I was thrilled as I'd seen her first film, Red Road, and loved it.

Q: Is it true that, like Woody Allen, she wouldn't give you the script before shooting?

A: Yeah, and it made me a bit nervous as I don't usually work that way. I like to really prepare, so it was a bit of a risk, but she seemed totally confident and in the end we compromised. She'd give me the next week's work on a Friday, so I had the weekend, and she was right - it worked out fine.

Q: Tell us about working with Kate Jarvis as the young girl Mia. She'd never acted or danced before.

A: She's obviously got a lot of Mia in her. She's tough as nails and not going to be taken advantage of. At the same time, she's very vulnerable and insecure. As for her acting, she's got this honesty and rawness and fantastic intuition. She's like a laser beam when you act opposite her. I was impressed.

Q: You were last seen in Inglourious Basterds. Any funny Tarantino stories?

A: All sorts. He's so shy and quiet. I tried to bring him out of his shell! No, I'd be lying if I said I wasn't star struck doing a scene with Brad Pitt and Quentin directing. You go, 'OK, get your shit together! Get a grip, man!' That's why I do so much preparation usually, so that when I freak out at those times, I can go, 'OK, relax!'

Q: You just shot Jonah Hex with Megan Fox. You know every 15-year-old boy hates you now?

A: I know, especially as I try to kill her in the film. I found that out at Comi-con. They really do hate me! It's a western based on a comic book, and she was great. Sadly I just had the one scene with her, and it was very physical and she was game for everything.

Q: Apart from fighting with Megan Fox, what's the wildest thing you've done recently?

A: I went diving with sharks when I was in South Africa. We had seven Great Whites in the water next to us. It was amazing, awe-inspiring.