American television director Dennis Donnelly is best known for his work on the television shows "Emergency!" and "Adam-12". Donnelly, the brother of fellow TV director Tim Donnelly, got his start working as an assistant director during the late 1960s, and transitioned to helming shows during the early '70s. Donnelly directed numerous episodes of "Adam-12" and "Emergency!", both tense procedural dramas co-created by Robert A. Cinader, helping to create the shows' realistic aesthetic. During this era, he also helmed the cult slasher flick "The Toolbox Murders". Other '70s programs to feature Donnelly as a director include the live-action superhero show "The Amazing Spider-Man", as well as the short-lived "Project U.F.O." and the popular series "Hawaii Five-0" and "Charlie's Angels". During the '80s, he helmed various episodes of "Hart to Hart", "The A-Team,", "Simon & Simon", and "Falcon Crest", and contributed briefly to other popular shows such as "Airwolf" and "Hunter". Largely inactive during the '90s, Donnelly retired later in the decade.