Sergeant Crowley is a police officer with the Los Angeles Police Department. On the morning of Sunday, 20 May, 1990, he was serving as watch sergeant at Hollywood Division. At 8:53 a.m. he called and paged Detective Harry Bosch at home to inform him of the discovery of a body in a pipe on the access road to Mulholland Dam at Lake Hollywood. He tells Bosch the call came in as an anonymous 9-1-1 a little after 4:00 a.m. but he did not send a patrol car to check it out until it was daylight. Crowley said he believed this was not a homicide but simply a case of a hype (heroin addict) overdosing because there was a similar case about a year earlier.