Gus’ expedition with Dr. Singh leads to several shocking discoveries. Big Man and Aimee seek refuge and reinforcements. Becky connects with a new friend.

Anna’s suspicions are aroused as Lydia prepares to host a party. Lauderback is blackmailed. In 1866, Crosbie Wells is buried.

Five-0 is baffled when a highly skilled ring of thieves pulls off a heist of an armored car, killing two security guards but leaving the money behind. Their only lead…

A barbaric family history is revealed when Nick and Hank investigate a case of breaking and entering. Meanwhile, Nick assigns Monroe to look after Aunt Marie.

The CBI investigates the death of a geologist, which Lisbon is convinced is the key to bringing down Tommy Volker.

Rose is taken home, but a spaceship crashes in the Thames and London is closed off… Enter the Slitheen!