Los Angeles, April 2 (IANS): “Fifty Shades of Grey” star Jamie Dornan says he stalked a woman on the tube rail to understand his role as a serial killer on the TV series “The Fall”.

Dornan's role as Paul Spector, a serial killer, challenged him to act like an actual serial killer in real life.

He told Los Angeles Times newspaper that he stalked a woman just to know how it felt like to follow and pursue someone who becomes a target to kill, reports aceshowbiz.com.

Dornan enjoyed doing things to support his practice in understanding the character. To follow and to stalk someone are something new that he had never done before and it gave him a new experience. Although he did not feel proud of himself in doing that dirty action, he admitted that he could learn something from the whole preparation process.

“It was intriguing and interesting to enter that process of 'What are you following her for?' and 'What are you trying to find out?' " Dornan said.

Despite his dedication to his role as serial killer, Dornan did not want to play a serial killer forever.