Reality star Spencer Pratt has said the forthcoming Channel 5 film about him and his wife, Heidi Montag, is like a real documentary that asks controversial questions.

Speidi: Scandal, Secrets and Surgery follows the successes and pitfalls of the couple's career - most recently they were runners up on Celebrity Big Brother.

The couple found fame in 2006 after appearing on the reality series The Hills, which followed a group of young people living in California's Orange County.

In an interview with MTV, Pratt said they decided to do the documentary because Channel 5 had treated them well on Big Brother.

He said: "I think Speidi's documentary for Channel 5 is special, it has the most exclusive access to the real Speidi and asks the most controversial questions in the interviews.

"It has the first interview with my mum in the history of media, with my older sister and little sister and my Nana, so I think it has some really major exclusive footage.

"We gave them such great access because Channel 5 was so great to us with Celebrity Big Brother and putting us on such a boring season to make it more entertaining.

"In the special, there is no game being played. It's really like a documentary, they asked us questions and we showed them our house and our family and our dogs.

Fake filed for divorce

"We tried to explain things we have done, so I would say it's not a game so it will look more real. But I think in Celebrity Big Brother, we were the most real in the history of any housemate."

The documentary includes interviews with Pratt, 29, and Montag, 26, where they offer answers about their plastic surgery, bankruptcy and their marriage.

In the film, Montag explains how they "only fake filed for divorce".

Speaking to Digital Spy, Montag said the Speidi documentary shows them in a "normal environment".

She explained there have been talks about her and Pratt doing their own reality show and that the documentary was a good "middle step".

Asked about how she would feel about not being famous, Montag said: "I would just like to have money, that's the main reason I wanted to be famous. I come from a really humble, small town and my family didn't hardly have rent money every month.

"To have an avenue to be financially independent and successful is the only reason I ever sought after fame ... actually I didn't even seek it, it kind of fell in my lap. It's not the fame part that I'm addicted to."

Speidi: Scandal, Secrets and Surgery is on Channel 5 at 10pm tonight (Monday).