It’s the small Canadian data firm credited with helping to take Britain out of the EU. But now Aggregate IQ are at the centre of another political storm – after this programme broadcast allegations that Vote Leave cheated. At question: more than half a million pounds paid to Aggregate IQ in the final weeks of the campaign. But who are they? And what role did they play in our exit from the EU? Paraic O’Brien has been to Victoria in British Columbia to find out.