Danny "Danno" Williams, while off-duty, pursues a gun-wielding crime suspect to the man's apartment. While shooting open the lock, Danny believes he inadvertently wounded the suspect fatally. Danny attends to the dying man whose drug-addicted girlfriend takes the gun which actually had been fired at Danny by another person and flees the apartment. Danny is soon indicted and jailed pending trial. McGarrett races to find the woman and exonerate Danny. It is later discovered that she is connected to Big Chicken, a smooth-talking formidable Honolulu drug dealer.
—Bill Koenig and Richard Birdsall