Justin Timberlake - I'm.Mortal Justin Timberlake?

Justin Timberlake has been offered the lead role in 'I'm.mortal'.

The 'Cry Me A River' hitmaker - who has just finished filming 'Bad Teacher' alongside ex-girlfriend Cameron Diaz - will star opposite 'Dear John' actress Amanda Seyfried in the science fiction project if he accepts the part.

The film - which is to be directed by Andrew Niccol - will focus on the idea of a society where people are unable to age past the age of 25, with those who wish to live longer having to buy extra time to extend their life.

Justin - who has also starred in 'The Love Guru', 'The Social Network', and 'Southland Tales' - will play a man forced to go on the run after he faces charges for murdering a person in the hope of stealing their time, Deadline.com reports.

Meanwhile, blonde beauty Amanda will star as his kidnap victim, who he decides to take on the run with him.

It was recently reported Justin is set to star in one of Guy Ritchie's new movies, with the British film director thinking he would be perfect for the big-screen version of musical 'Guys and Dolls'.

A source explained: "Work is really taking off for Guy at the moment and he is lining up talent for projects in the pipeline.

"Guy and Justin have known each other for a while through Guy's ex-wife Madonna."