Liv Tyler joins The Side Effect

Liv Tyler is set to star in medical drama 'The Side Effect'.

The 'Lord of the Rings' actress will play a woman named Catherine Rigby who spends several months alone in space for a global pharmaceutical company, only to find herself inexplicably pregnant in the film, set to be helmed by Ti West.

Ted Hope and Peter Phok will produce the picture.

Commenting on the part, Liv said: 'West is a super-talented, exciting young filmmaker. The role of Rigby is a fantastic character within a great thriller and I am looking forward to sinking my teeth into the part.'

Ti is best known for horror films - including 'Cabin Fever 2: Spring Fever' and 'The House of the Devil' - and he says his experience will play part in the new movie.

He told Deadline.com: 'Although it is still somewhat of a horror film, it is much more psychological than any of my previous efforts.

'It was essential that I find an actress who could portray a wide range of emotion and always earn the audience's sympathy no matter what the situation. As soon as I sat down with Liv, it was obvious she was the one.'