Danny and McGarrett fill in as security for Danny's former mother-in-law, the romance novelist Amanda Savage. She and Danny had never gotten along. Brad Chen was hit by a semi after walking into traffic. Noelani said he was on steroids at the time and he would have been killed by the combination of drugs if the truck hadn't hit him. Amanda and Steve get along fine, to Danny's chagrin. Brad's father said his baseball career had gotten derailed by injury. He wasn't shocked that Brad was using steroids. Tani and Junior find empty vials and bags of blood at Brad's apartment. Grover suggests Brad may have died from a bad batch of steroids and there may be more out there. Grover sends Tani and Junior undercover at the gym where Brad worked out, him as a member and her as an aerobics instructor. Junior asks member Derek about getting juiced. Derek and two others attack Junior, but he takes them out and arrests Derek. Brad stole a master key and a vial from a locker. Adam gets the name of Moses Pocheho as the drug dealer. Moses tore his house apart, fought with cops, then dropped dead of a heart attack, likely from the bad steroids. Grover and Adam find more blood in his fridge with different initials on the bags. Moses was the target of the tainted drugs. Matt Zenner was recruiting young blood donors for Moses, but he had recently cut Brad out from his operation. McGarrett takes Amanda to Kamekona's. Steve talks up Danny to Amanda. Moses was trading blood for steroids. Dr. Niles Werner was using the blood for an immortality treatment. Werner injects Tani then escapes and she seizes. Adam finds a defibrillator and adrenaline to save her. Grover shoots Werner in the leg. Danny and Amanda make peace.