The actor, who will also produce the film, will star as aspiring lawyer Kyle McAvoy, who is forced by criminals to work at the world's largest law firm to spy on a major contract.
Shia LaBeouf was previously attached to star when Paramount first bought rights to the novel in 2008, but has since left the project.
The film will be the first major picture the 26-year-old has produced, having served as an executive producer on this year's That Awkward Moment.
The movie has secured Oscar-nominated director Adrian Lyne, whose previous films include Fatal Attraction (1987), Indecent Proposal (1993) and Lolita (1997).
William Monahan will write the screenplay, which will be Grisham's seventh novel to get adapted for the big screen.
Efron became a household name after the release of High School Musical in 2006, in which he played protagonist Troy Bolton.
He has since taken on more dramatic roles in The Lucky One (2012) and The Paperboy (2012), and will soon be seen in comedy Neighbors alongside Seth Rogen.Reuse content