Based on an actual serial arson investigation that took place in Glendale, CA, in the late '80s and early '90s.
Ray Liotta stars in the film as John Orr, a skilled arson investigator with a sixth sense for finding the "point of origin," the place where a fire was started. Orr also has a knack for locating the devices used to start the fires. Keith Lang (John Leguizamo), his ambitious young protégé, calls Orr "Professor." Orr is stumped by a series of big fires, some fatal, which seem to have been set by the same arsonist.
A commission is appointed to investigate the case, headed up by ATF agent Mike Matasso (Colm Feore) and fireman Mike Camello (Cliff Curtis). Orr uses his influence to get Lang appointed to the panel. But Matasso and Orr are immediately at odds with each other, as the ATF man seems to resent Orr's efforts to maintain control of the investigation.
Orr is also dealing with his troubled marriage to Wanda (Bai Ling) and is having an affair with the volatile Kate (Illeana Douglas). As he gets deeper into the case, trying to get inside the head of the criminal, Orr begins to worry that the arsonist has some kind of personal involvement with him. Then the commission uncovers a link to an earlier string of fires, and uncovers evidence that the arsonist may actually be a fireman.