(Cover) - EN Showbiz - Bradley Cooper loves girlfriend Rene Zellweger, and says working with her made him realise how much he enjoys his job.

The pair first met when they were shooting horror movie Case 39, which is released in America next month. They have been dating for around a year, but are fiercely private about their relationship. Neither will discuss the intimacies of their romance, but both were happy to heap praise on each others acting skills.

Rene plays Emily in the movie while Bradley is Doug. Emily is a social worker who decides to give a young girl a home, then calls on her friend Doug, a psychologist, for support when she begins to worry the child has problems. Both stars thoroughly enjoyed the filming experience, and say it was meeting each other which made it special.

Can't say enough about her, Bradley told Entertainment Tonight. I never met her before this movie, but I just love her. I love coming to work. I love acting with her. I can learn so much from her. It's just so easy to work with her!

Rene added: He's a great actor! I just got so excited, not believing that I was going to go work with him.

The actress was also thrilled to be making a horror movie. She loved working in the genre, explaining she didnt expect to find being frightened every day so enjoyable.

It's so fun to be scared," she laughed. "It's so fun to go and see a film that manages to make you uncomfortable, and yet you don't want to walk away from it; you still want to watch it and have that experience." (C) Cover Media