Sam Lucas, in Ghost Whisperer, is portrayed by both Kenneth Mitchell & David Conrad. Sam died in an accident soon after Jim died. His spirit crossed over, giving Jim the opportunity to take over his body and continue living. As he transferred to Sam's body, Jim's memory of his old life was completely erased. He soon moves into Melinda's garage, feeling as though he could only trust her; he had a strong bond with her, but doesn't know why. As time progresses, Jim begins to recall certain memories. Some memories are Sam's, and others belong to Jim. He is confused and tormented until Melinda confesses, "Your memories, the reason that you can't make sense of them, is because they're not yours. They belong to a ghost! Someone who died and then went inside Sam's body. You're not Sam, anymore ... you're Jim! My husband! Or at least what's left of him." Knowing this causes him to pull away from Melinda, breaking her heart.
He was born on July 7,1978. His sister followed 4 years after. As a child, he almost drowned in the lake his family visited. At some point in college he became interested in architecture. He dated Nikki during and after high school on and off, but was never willing to make a commitment.
Melinda's son, Aiden, is given the middle-name of Lucas to commemorate Sam. Sam Lucas becomes a doctor and at some point adds the middle name of James and goes by Jim.