 The armorer from the Rust movie set is expected to take the stand as Alec Baldwin's involuntary manslaughter trial enters its third day. Prosecutors plan to call Hannah Gutierrez to testify to grill her about the shooting that killed cinematographer Helena Hutchins. Gutierrez is already serving an 18-month sentence for failing to secure the gun. Today, she's expected to plead the fifth. ABC's Danny New.