After Steve receives a posthumous letter from his mother that contains a cypher, Danny is attacked by someone willing to kill to steal it; Five-0 must help an anonymous good Samaritan who's in the crosshairs of some very dangerous people.

Cast: Alex O'Loughlin, Scott Caan, Ian Anthony Dale, Meaghan Rath, Beulah Koale, Katrina Law, Taylor Wily, Dennis Chun, Kimee Balmilero, Chi McBride, Lance Gross, Diana Lu