Danny's British socialite ex-mother-in-law Amanda 'Mandy' Savage, a famous romance novelist, arrives to present her latest work, but her regular security agent is out due to passport problems, so she commandeers ever-despised Danny, who gets McGarrett to come along, meet and like her -mutually, on first name base, as she digs a sexy former SEAL officer and gentleman- and act as her chauffeurs. Danny and Amanda initially butt heads but finally make up, both wanting the best for Rachel. Five-0 investigates a series of lethal steroid injections going around Honolulu. The initial fatal OD victim inadvertently robbed the wrong drug from the actual suspect dealer, whose trail leads to a gym, where super-fit Junior and Tani go undercover at a local gym as potential buyers.
—KGF Vissers