David's character is Marty Lang is a former Metro-Dade Vice detective and partner of Hank Weldon, so close Lang's son called Weldon "Uncle Hank". During their partnership Lang worked with Weldon to bring down drug dealer Tony Arcaro, a three year case which was lost on an unspecified technicality in 1979, freeing Arcaro, after which he disappeared without a trace. Lang and Weldon broke their partnership when Weldon left the force, in mental distress. When Weldon resurfaced in 1985, Vice Detectives James "Sonny" Crockett and Ricardo "Rico" Tubbs went to see Lang, now working in an unspecified federal job, who told them the story of how Weldon left the force, went into mental rehab, then a hospital, and was surprised that he was allowed out of the hospital, then angrily demands Crockett and Tubbs leave. It was discovered later why Lang felt that way...he knew Weldon had killed Arcaro after the dealer's release from jail and entombed him in a wall (which Lang helped build) in an abandoned building, showing his loyalty to his former partner.