Five-0 investigates when a rancher is murdered after he uncovers human skeletons on his property where legend says that Civil War-era gold coins were buried. Also, Quinn's former stepdaughter, Olivia, reaches out to her for help after her father doesn't come home.

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