McGarrett and Danny hold a soft opening at their restaurant for their fellow cops. Duke introduces Steve to Milton Cooper, his grandfather's old partner. Milton tells McGarrett that his grandfather would have become a cop if he hadn't been killed at Pearl Harbor. Milton gives Steve his grandfather's briefcase, which holds the last unsolved case of legendary HPD Detective Chang Apana. It was a missing-persons case, involving a poor girl named Lila. McGarrett falls asleep and dreams about his grandfather's time. The older McGarrett and Milton get shot it in front of HPD headquarters. Asked about the necklace Lila was wearing, her brother Evan points McGarrett and Milton to plantation owner William Pettifer. Pettifer said Lila gave him $300 toward her father's debt to him. McGarrett and Milton chase the men who had shot at them into a cane field, leading to a fiery crash. McGarrett confronts crime boss Earl Blackstone. McGarrett and Milton interview singer Alexa Alana, a friend of Lila's. Alexa is shot and can only give the first name of Lila's boyfriend -- James. Captain Sumner suspends McGarrett and Milton for continuing to pursue Lila's case. They determine that Lila's boyfriend was James Whitmour, but he was gunned down the same day she went missing. One of the thugs killed in the chase crash worked for Whitmour's father Clarence. McGarrett, Milton, and Flanagan confront Clarence at his compound. Clarence is about to tell them what happened to Lila when the sirens for the Japanese attack on Pearl Harbor sound. Steve awakes in the present. Steve thinks James' shot-up car and Lila's body are buried under the site where a pool was to be built on the Whitmour estate. Danny and McGarrett agree to sell out to Kamekona and leave behind the restaurant.