[2] He graduated in 2001, and has acted both at Teatret Vårt in Molde (2001–2002) and at Oslo Nye Teater (since 2002), where he has been in plays such as Hamlet and Kvinnen Som Gifftet Seg Med en Kalkun (The Woman Who Married a Turkey).

Although the director, Jens Lien, originally thought Hennie was too young for the role, the actor convinced him he was the right man for the film.

For this role, Hennie and his co-star, Nicolai Cleve Broch, undertook six months of hard physical training in order to perform convincingly as bodybuilders.

[6] In 2011, Age of Heroes was released, a World War II film primarily shot in Norway.

Hennie plays the main role as a commercial offshore diver in the North Sea during the 1970s who witnesses an accident while diving under extreme conditions, prompting him to search for answers.