Universal Pictures and Tom Shadyac ("Liar, Liar", "Bruce Almighty") will bring to the bigscreen the true story of John Francis, who walked from one end of the country to the other and didn't speak a word for nearly two decades reports Variety.

After witnessing a collision of two oil tankers that wiped out the ecosystem in San Francisco Bay in 1971, Francis boycotted motor vehicles and took off on foot for a cross-country pilgrimage to raise environmental awareness, taking a vow of silence that lasted 18 years.

He finally broke silence when he defended his Ph.D. thesis, which he wrote on the subject of oil spills. Shadyac will develop the film to direct, whilst Justin Zackham will write the script based on Francis' memoir "Planetwalker".