Global movie superstar Robert Downey Jr has donated an once-in-a-lifetime raffle prize to help raise money for a new children’s hospice in Wiltshire.

Robert Downey Jr
The movie star has given animpressive red carpet pass as a raffle ticket

The Iron Man star has offered one lucky winner the chance to walk down the red carpet with him at the Los Angeles premiere of the latest Avengers instalment, Age of Ultron, before joining the American star for a helicopter ride over the city.

Dorset-based charity Julia’s House, which currently offers home-based community care, is planning to build a £3million children’s respite care hospice and had an original financial target of £500,000.

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However, after Downey’s announcement the website crashed and the possibility of a higher fundraising amount significantly increased.

Speaking of the prize, Downey Jr said: "Have you had the best night of your life...yet? Well you could, with me, for a good cause.

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"You donate $10 or more for a chance to win the RDJ experience and I will proceed to awesome the c**p out of you.

"We’ll giggle, chat, take pictures and perhaps even engage in a battle of wits."

Film director Guy Ritchie also helped to raise funds for the project and organised a private clay shoot and auction at his home on the Dorset-Wiltshire border last summer.

For a chance to win this amazing prize, visit www.omaze.com.