Soderberg's Unsane premiers in Berlin
Unsane tells the story of a successful young businesswoman who believes a man from her past is stalking her. She suddenly finds herself trapped in a mental institution against her will and the stalker is amongst the nursing staff trying to manipulate her.
The movie was shot with an iPhone and Leonard says it has a definite theatrical feel: "We really approached it like a play sometimes because the scenes were so long, but it's fun doing it with these guys."
Soderberg says he has a very 'hands-off' approach to his actors.
"I try to leave them alone as much as I can," he explains. "I think you'd be surprised at how little I talk. We discuss it beforehand, but once we get on the set we just go to work."
Foy says she found the filming itself claustrophobic.
"We were shooting in the same place for 10 days and we were shooting pretty rapidly," she says. "It did feel like we were all in some sort of wierd Steven Soderburg institution that he'd created."
The movie will be released in Europe in March