Idris Elba found making 'The Mountain Between Us' an ''interesting therapy session''.

The 45-year-old actor - who has two children Isan, 16, and Winston, three, from past relationships - spent a lot of time filming in isolation with 41-year-old co-star Kate Winslet, who has three kids from three marriages, and they got close by swapping stories about their personal lives so they could make their bond seem more ''realistic''.

He said: ''We both come with life experience, to say the least, like our characters do.

''And that's great because you don't have to make that s**t up.

''Kate and I talked about all the times we've fallen in love, and what those feelings are like.

''I wanted it to be relatable. Of course, it's a survival movie and what's the plausibility of people people landing on a mountain? Making love and all that? We wanted to make it realistic.

''It was an interesting therapy session for me.''

The 'Beasts of No Nation' actor feels ''lucky'' because he has been able to avoid racial stereotypes in his work and got his big break at a time when he wasn't being typecast.

He told Red magazine: ''I avoided being stereotyped from a young age because I didn't want to play one character for the rest of my life.

''I don't just want to play bad guys or the funny best mate.

''I was lucky because I was part of a young set that were breaking through at a time when producers would actually say, 'I want a black guy for this character' [even if it wasn't in the script].

''Chiwetel Ejiofor was coming up at the same time Back then, if you hadn't been to drama school, you weren't getting anywhere.

''And here I was, no knowledge of Shakespeare but I was going up against all these boys from drama school and getting work.''