Behind the scenes as the National Portrait Gallery reopens

The cost was originally supposed to be £35.5 million. In fact it has come in at just over £41 million. But that overspend, Cullinan says, was deliberate, after the gallery received an “extra” £10 million donation from Leonard Blavatnik, the industrialist who has become Britain’s most generous arts benefactor. “Doing what we wanted to do for £35 million was always going to be tight,” Cullinan says. “The extra money from the Blavatnik Foundation enabled us to concentrate on quality.”