Rudd on This Is 40 'family affair'

Paul Rudd has opened up about the family atmosphere that ruled on the set of This Is 40.

The sequel to 2007's Knocked Up is directed by Judd Apatow, stars Judd's wife Leslie Mann alongside Paul, and features the couple's daughters Maude and Iris.

"We're both of us in this movie in somewhat compromising, vulnerable positions, and doing things that are a little embarrassing or whatever," Paul explained.

"If you wanted to try and show the real nuts and bolts of a marriage... you want to hopefully be surrounded by people who have your back, people you can trust and people you have a history with."

The movie sees Paul and Leslie's characters Pete and Debbie as they navigate their way through marriage, growing children, ageing parents and uncertain careers.

Paul continued: "There really is this sense of familial spirit and it makes shooting this, one, a lot more fun but two, a lot easier, because of that history."

Leslie added: "We feel so safe in that environment that we end up doing things that we regret later.

"We're like, why not? This is a safe space."