Peter Farrelly directing a film about the making of Rocky

Peter Farrelly is to direct a film about the making of 'Rocky'.

The 67-year-old filmmaker is to helm the movie 'I Play Rocky', which tells the story of how Sylvester Stallone bet on himself to play the career-defining role in the 1976 sports film.

A logline for the project reads: "A struggling actor with a partially paralysed face and a speech impediment writes a script that a big movie studio wants to buy, but he refuses to sell it unless he gets to play the lead.

"Turning down an offer of life-changing money, he instead works for pennies to get the movie made with himself in the starring role.

"The movie becomes the biggest box office hit of 1976, notching 10 Oscar nominations and winning Best Picture. The true story of the making of the iconic movie 'Rocky'."

'Green Book' director Farrelly is producing the flick alongside former Warner Bros. Motion Picture boss Toby Emmerich and Christian Baha – while Peter Gamble is penning the script.

Emmerich said: "I've been a fan of Peter Farrelly as both a filmmaker and a person since getting to work with him on the music for 'Dumb and Dumber'.

"But it was 'Green Book' that made me think of Pete for this inspiring screenplay. Christian Baha and I feel blessed to have Pete at the helm for this movie.

"And like the unknown Stallone starring in 'Rocky', Pete will be conducting a worldwide search to discover another actor who just needs one shot – in 'I Play Rocky' – to show the world what he can do."

Baha added: "When I first read Peter Gamble's energetic and poignant script, I knew it captured something very special. The story of 'I Play Rocky' is as unique as Sylvester Stallone himself, a seeming Everyman with an undeniable gift who needs to share it with the world and refuses to take 'no' for an answer."