Baltimore police officer Fia McKee is put on leave for excessive use of force after interfering in a crime that turns deadly. Given a second chance, she is sent to work undercover for the Thoroughbred Racing Protective Bureau (TRPB) at the Gulfstream Park in Florida, where she works as an exercise rider. Her assignment is to watch and report back on two racetrack workers who have been suspected of illegal activities and whose horses continue to outperform all expectations, winning their owners unseemly amounts of money in the races. To complete her cover story, Fia moves in with her semi-estranged brother, Patrick, who lives near the racetrack. Her investigations are complicated when her niece, Jilly, disappears after a shadow gang takes Jilly's beloved horse. Now Fia must work two angles—first to find out what's really going on with the men who might or might not be gaming the system, and second to bring the men who prey on horses to justice. Along the way, Fia encounters Cuban gangs living off the grid, a (very handsome) do-gooder who's close on their trail, and a cabal of super wealthy gamblers who will stop at nothing to ensure they always win.