Producers asked Caleb and Cody Walker to fill in for their brother and help complete the movie's seventh instalment after he died in a fiery car crash in November 2013.

His face was digitally superimposed onto his brothers' performances for scenes that Walker had not yet shot and in a modified ending in which his character Brian O'Conner drives off into the sunset.

The character remains alive in the fictional Fast universe and is mentioned twice in 2017's The Fate of the Furious.

"I just hope we get to - I don't know - have a little cameo and bring Paul back to save the day and I get to help create that again," Caleb Walker, 40, said.

"That's my dream and I hope we get to do that in one of the future movies."

"I think there could potentially be a way to do it. But it would take a lot of thought and it'd have to be tasteful. It would have to be tasteful," Cody Walker, 30, said.

Caleb and Cody Walker are promoting I Am Paul Walker, a new one-hour documentary about the actor's childhood, family and career.

Walker was 40 years old when the Porsche Carrera GT he was riding in spun out of control, struck three trees and burst into flames on a street in California, killing him.

Australian Associated Press