Use a Gun, Go to Hell

S12, E7: In a powerful episode playing upon the easy availability of handguns, McGarrett and his Five-O unit follow the trail of pain and death left by one of the weapons, hoping to recover it before it can wreak yet more havoc. The wounding of a florist by a pistol-wielding bandit results in the first break for McGarrett in his stymied search for the assassins of an Hawaii state senator.