New Line Cinema acquired the rights for an American live-action film adaptation of Monster. Academy Award-nominated screenwriter Josh Olson (A History of Violence) was hired to write the screenplay. Although the studio initially announced a 2009 release, the project apparently fell into production limbo.
In 2013, it was revealed that Guillermo del Toro and American premium television network HBO were collaborating on a pilot for a live-action TV series based on Monster. Co-executive producer Stephen Thompson (Doctor Who and Sherlock) was writing the pilot, while del Toro was to direct it and be an executive producer alongside Don Murphy and Susan Montford. In 2015, del Toro told Latino-Review that HBO had passed on the project and that they are in the process of pitching to other studios.