Alec Baldwin was on the set of his new movie “Rust” when he discharged a prop firearm that killed Halyna Hutchins, the film’s director of photography. Director Joel Souza was also injured in the incident and transported to a local hospital. The Santa Fe County Sheriff’s Office said the investigation “remains open and active” and Baldwin said he’s “fully cooperating with the police investigation.” No charges have been filed. Hollywood weapons expert Larry Zanoff walks Anderson Cooper through how prop guns are usually handled on film sets and the safety guidelines that go along with them. Plus, experts say the notebook found near Brian Laundrie’s remains in a Florida nature reserve park could shed some light on the details surrounding his disappearance and the violent death of his fiancé, Gabby Petito. CNN National Correspondent Randi Kaye joins AC360 to give an update on the investigation. Airdate: October 22, 2021 Guests: Larry Zanoff & Randi Kaye. To learn more about how CNN protects listener privacy, visit cnn.com/privacy