A screenwriter (Lethal Weapon 2, The Eiger Sanction) as well as a novelist, his work won a dozen national awards, including multiple Edgars and Shamuses.
[citation needed] Murphy was one of the authors of the screenplay for The Eiger Sanction in 1975, and also co-wrote (with series creator Shane Black) the original story for Lethal Weapon 2.
Murphy also shared writing credits with Cochran on The Forever King and several novels under the name Dev Stryker.
Some of his solo novels include Jericho Day, The Red Moon, The Ceiling of Hell, The Sure Thing and Honor Among Thieves.
Together with Gerald Welch, he created a Destroyer spin-off series called Legacy, about Remo's children Winston "Stone" Smith and Freya Williams.