"Both of them really relish the opportunity to show off their comedic chops. They've got real presence and timing," says Wright. "It was more interesting for me to cast people that you maybe know from another genre. They also had to pose a real physical threat to Michael Cera and I think if I'd had people that you would think off as comedy actors in those parts it might have been different. I wanted it to be interesting matches in terms of the exes and Michael."
As to the film, which is still unreeling internationally, he adds, "It's taking the trials of love and presenting them as a visual metaphor. The inspiration for the book by Bryan Lee O'Malley was the idea that when you date someone you demonise their exes. Whether that is true or just in your mind, the idea just snowballed from there. It wasn't a superhero film or a generic sci-fi tale, it was essentially, deep down, a date movie, a rites of passage."