Other mistake: In Saw II, Jigsaw shares a story with Detective Matthews about how he attempted suicide after his cancer diagnosis by driving his car off a cliff. We then see Jigsaw pulling a metal rod out of the left side of his stomach. However, no puncture wound/scarring is visible on Jigsaw's stomach when his autopsy is being performed. (00:00:50)
Saw IV (2007)
Trailers
Directed by: Darren Lynn Bousman
Starring: Tobin Bell, Betsy Russell, Costas Mandylor, Scott Gordon-Patterson, Scott Patterson
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More mistakes in Saw IV
Agent Strahm: We're here to find the person helping Jigsaw and Amanda Young.
More trivia for Saw IV
Question: A glass casket with a key inside it is shown in John's warehouse. What does that mean?
Answer: This was revealed by director Darren Bousman to have originally been used in a now-deleted (and not released as of Oct. 2020) scene in the movie. The glass box is used for what is (most likely) a different purpose in Saw V.
Answer: It plays an important role in the next few movies.