Grover must prevent a man who is accused of killing his wife from committing suicide.
McGarrett and Danny investigate the murder of a private detective whose client was killed the same way, Adam sends Jessie into a dangerous situation with disastrous consequences, and Danny's uncle comes to town to help with the restaurant.
Tani and Junior go undercover as prospective parents to infiltrate a private school where the headmaster was murdered, and Adam's life is on the line when he is held captive and forced to produce a massive amount of money.
The task force investigates a series of social media conspiracies that simulate dangerous public attacks; when a top-secret government programme is stolen, the team works to uncover the Troll Farmer's involvement.
The task force races against the clock to recover a valuable asset stolen from the government; Red hatches a plan to help track down the perpetrators.
