Oscar-winning actor Sir Ben Kingsley is mugged in a new short film as part of the campaign to impose a "Robin Hood tax" on banks' financial transactions.
The star of Gandhi and Shutter Island is cornered in a dark car park by a group of "Robin Hoodies" and forced to hand over his possessions.
The campaign is calling for an average tax of 0.05 per cent, equivalent to 50p in every £1,000, on share, bond, currency and derivatives transactions between financial institutions such as investment banks and hedge funds.
Campaign groups say this would raise hundreds of billions of pounds to help poor people at home and abroad.
Sir Ben said: "At a time when people at home and abroad are suffering economic hardship, our politicians should listen to the voice of ordinary voters. A tiny tax on banks could make a massive difference to poor people."
The campaign is a collection of more than 100 domestic charities, aid agencies, green groups, faith organisations and unions, including Oxfam, TUC, Barnardo's, The Salvation Army, Friends of the Earth, ActionAid, RSPB and Crisis.
A number of economists and celebrities have backed the campaign since it was launched earlier this year.