Boam's profile in Hollywood increased in 1989 when he wrote the final screenplay for "Lethal Weapon 2" and subsequently co-wrote "Lethal Weapon 3" (1992) as well. In between, came the highly entertaining "Indiana Jones and the Lost Crusade" (1989), which some critics felt was the most full-bodied of the three "Jones" films. In this one, the audience was introduced to Sean Connery as Harrison Ford's father and also saw River Phoenix as a young Indy giving backstory on the character. Boam's work in TV has been sporadic due to his feature film assignments, but he did form Boam/Cuse Productions in 1988 with Carlton Cuse, in part to do some TV work. Subsequently, Boam wrote the pilot for and was one of the executive producers on the short-lived "The Adventures of Brisco County, Jr." (Fox, 1993). He also made his TV directorial debut in 1993 helming an episode of HBO's "Tales From the Crypt," in which a girl is tricked into becoming the sacrifice to a mummy but turns the tide on the trickster. In 1996, Boam acted as co-producer and screenwriter of "The Phantom," inspired by the Lee Falk comic strip. At the time of his death, he reportedly had completed a script for the fourth installment in the Indiana Jones films.