After actor Paul Walker died in a car crash in 2013, the fate of Furious 7 came into question, since it had barely begun filming. Through a mixture of CGI and the assistance of Walker's brothers as doubles, the filmmakers recreated his character for the 2015 film.
In a Hollywood Reporter article, the filmmakers explained the basic process. In some shots, camera angles were used to conceal the fact that one of Walker's brothers was doubling for him. In others, which required clear looks at his face, the process was more in-depth. Caleb or Cody Walker would perform the scene, then filmmakers would composite it with pre-existing footage of Paul Walker, often re-lit and re-edited, or a CGI recreation of his face, using the previous footage and digital scans of the Walker brothers as references.