A fourth film was released in 2008, "Indiana Jones and the Kingdom of the Crystal Skull". It features the return of Allen and introduces Shia LaBeouf as her son with Jones, Mutt Williams. The setting moved from the 1930s to the 1950s, pitting Jones against Russians to recover a Crystal Skull. The film was a financial success but polarized critics and fans. It also originated the term "nuke the fridge", a reference to a derided scene where Jones hides in a refrigerator to survive a nuclear blast. As they did with "Temple of Doom", Lucas and Spielberg have defended the film and apologized for its reception. A fifth film is in production as of 2020.