Jack Killian is a former San Francisco police detective who quits the force after he accidentally shot his partner dead in a confrontation with armed criminals. After lapsing into alcoholism, Killian receives an offer from Devon King, the beautiful and wealthy owner-operator of KJCM-FM, to become "The Nighthawk", host of an overnight talk show, taking calls from listeners and acting as a detective solving their problems during the day (the title of Killian's show would later be adopted in real life by talk-show host George Noory on KTRS in St. Louis from 1996 until 2003, when Noory took over from the retiring Art Bell as host of the nationally syndicated Coast to Coast AM). Even though Killian snapped that he doesn't listen to FM radio, he accepted the offer.