Strong Hawk: My Sister's Keeper is about a family of sisters who lost their parents over a decade ago and now discover they have powers. They attempt to help their community by acting as vigilantes but their heroic efforts make the ladies vulnerable to their natural enemies. This begins a journey for them to unravel family secrets and test themselves to see if they are really heroes.

When Bruce reluctantly follows his pal Oswald to the horse races and gets a taste of success, he quickly gets bitten by the gambling bug. But later that night at a poker game with some shady characters, he gets more than he bargains for when Oswald loses a hefty bet he can't cover. With Oswald's family held hostage, Bruce is forced to pay the remainder of his debt by robbing the payroll office in a Reno casino but not before he spirals into degeneracy and loses big himself during the job. When complications arise during the heist and Bruce must take hostages of his own, his desperation worsens as he takes a final stand against the mob to get Oswald's family back.