McGarrett, Danny, Tani and Junior are still still in quarantine after being exposed to a bioweapon. A man in a biohazard suit comes in and holds them at gunpoint. The man shoots Danny, then himself. Danny starts hallucinating about the future. First up is Grace's wedding to Will. The man also placed a bomb on the door. McGarrett and Junior administer to Danny, using the gunman's mask to get Danny oxygen. Tani floods the bathroom in hopes thst someone will come to investigate. A nurse comes, and McGarrett orders medical help and a bomb squad. Danny's next fantasy is Charlie graduating from the policy academy. Tani and Junior are a couple then, and she's the head of Five-0. Then Danny crashes again. He fantasies about Adam and Kono's baby. A surgeon walks McGarrett through cutting open Danny's chest. They then move Danny so the bomb squad can blow a hole in another wall. The hole is too small, so Grover goes at it with a sledgehammer. Medical personnel rush Danny to the operating room. Jerry couldn't find the gunman or his gun in the system. While he's crashing on the operating table, Danny hallucinates about elderly versions of himself and McGarrett. Everybody ribs McGarrett about his crewcut. The surgeon tells everyone that Danny is going to pull through. Jerry found the gunman's motel room. All that was there was a photo of Danny with the words "He deserved to die" written on it.