Viggo Mortensen on playing Sigmund Freud in his new film
3 February 2012 Last updated at 16:19 GMT
Viggo Mortensen stars as Sigmund Freud opposite Michael Fassbender's Carl Jung in A Dangerous Method.
The Lord of The Rings actor told Radio 5 live's Simon Mayo how David Cronenburg offered him the part and why he bought a number of the props used in the film.
A Dangerous Method clips courtesy of Lionsgate Films. The movie is released in the UK on 10 February.