A highly skilled heist of an armored car ultimately dumped in the ocean puzzles McGarrett and the Five-0 team when they learn the thieves left the money. Their only lead is a group of workers nearby, dressed in similar clothing; using facial recognition, they identify one as a former con, who tells McGarrett he responded to an internet ad for workers. Tracing the IP address for the job posting takes our team to a chiropractor's office used illegally during off-hours for drug doping for athletes. McGarrett and Danny get a name and an address for a woman they suspect is part of the heist crew, but they have no evidence connecting her to the crime, so they decide to conduct surveillance on her. Unfortunately, her house is in no parking zone and a surveillance van would stick out; fortunately, the house is also across the street from Danny's ex-wife's and she reluctantly gives permission for them to conduct their stake out. McGarrett and the team figure out this is a crew of highly trained athletes who conduct heists during triathlons. They also figure out that the crew stole the black box camera info from the armored car that has all the pass codes for every location on its run, so they effectively have the keys to any number of high-end jewelry stores and banks. With no concrete evidence to prosecute, our team continues to follow them as the triathlon starts. The heist crew disappears during the swim portion of the triathlon and Five-0 finds them and thwarts their escape.