The original Darth Vader actor Dave Prowse will be heading for Corsham this weekend for the annual sci fi family fun day.

The charity celebration of all things science fiction will take place at the Corsham School on Saturday, with Mr Prowse among the special guests mixing with Minions from the hit children’s film Despicable Me, Daleks, droids and blue-skinned alien priestesses Ady Davies, chairman of the Corsham-based charity sci-fi group, said: “It’s all getting really exciting. We have got some amazing guests this year.”

Bristolian actor Mr Prowse played the iconic villain in the original Star Wars trilogy, as well as the Green Cross Code man in public information films. Mr Davies said: “He’s bringing his Green Cross Code robot that used to help him cross the road. He found out we’re a family-orientated day, so he went down to his shed and dug it out for us.

“We’re also going to be joined by Farscape actress Virginia Hey, who was also in Mad Max 2.

“There’s all the Doctor Who people, including John Davey, who has played monsters in more episodes than any of the Doctors.’’ The group is hoping to match last year’s total of more than 4,000 people through the door, and aims to raise £1,700 for each of its four chosen charities.

Mr Davies said: “We’re supporting Wiltshire Young and Marie Curie Cancer Care, which is an under-appreciated cancer charity.’’ The event starts at 10.30am until 4pm, with free parking in all Wiltshire Council car parks in Corsham. Tickets cost £4 for adults, £3 for children and under-fours go free.