"Saw IV" is a horror film released in 2007, directed by Darren Lynn Bousman. It is the fourth installment in the Saw franchise, continuing the story of the infamous killer known as Jigsaw. The film explores the aftermath of Jigsaw's death and introduces new characters who are forced to confront their past sins through deadly traps. The plot intertwines with flashbacks that reveal more about Jigsaw's history and his apprentice, Amanda Young. As detectives work to uncover the truth behind the ongoing killings, they must navigate a series of gruesome challenges that test their morality and survival instincts.