Professor Payne went on a trip for a long time. In "Big Chills", Melinda helps a ghost that has to have the truth come out about an accidental death on a boat. In the next episode, Melinda finds a man that is dead and trapped in an online chat game. She soon realizes that the man is actually the teenager's father, who is trying to protect his daughter from an online predator. Melinda and Jim went on a trip to find another ghost (or many on the boat), but the main reason is to talk to the boat owner's son, who is planning to tear down the boat and rebuild it. Many spirits were worried that their home would be ruined, so they were bothering Melinda to help them. But one girl needed help to talk to the owner of the boat about the accidental death, when she waited for him in the same room she met him many years.
Then Melinda meets a teenage ghost who dies on the tennis court from a blood clot in her lung and Melinda watches the dead teenager follow her friends' family home (both families used to be friends, but one moved away and they stopped talking, and the families are no longer friends.) The two families soon find out that the hospital made a mistake and they switched the girls at birth. In the end Melinda and Jim think she is pregnant, but are disappointed when they get they discover that Melinda had a miscarriage. This episode is the episode of which the tagline is: The episode that will change everything.
In this episode Melinda and Jim goes to the woods and they stay in a cabin for Jim's friend's wedding. The spirit wants the bride to play a game which will let her know the truth about her fiance. She discovers that the ghost (Owen) used to know the bride when they were young. When she finds out the truth, she calls off the wedding. Later Jim goes back to clean up and finds the groom still in the cabin, with a gun. Melinda finds out and calls a detective. When Melinda and the Detective get there they see two shadows through the door windows and they see one man with the gun and one man without. Then the detective pulls out the gun and shoots. Then in the window Jim falls. Melinda is in the hospital waiting for Jim to wake up from the surgery. Then when Melinda wakes up she sees Jim's ghost. He says "Remember me this way; I'll always love you" Nurses suddenly rush in, and Jim begins to flatline.
In the next episode Jim keeps saying throughout that he is will not crossover, no matter how hard Melinda tries. There is a teenage ghost who keeps saying she's sorry and that it's all her fault that Jim is dead. It turns out that the teenager was anorexic and that made her heart stop. Her stepfather was very depressed, and he went back to work before he was ready to. Later we find out that the girl's stepfather is the detective who shot Jim. Melinda says to Jim "You have to do the right thing." He replies "I will." and possesses a dead man's body Sam to live again in episode 4.07 "Threshold". After Jim jumps in Sam's body he has no idea who he is.
Melinda begins dating Jim/Sam in episode 4.14 "Slow Burn" when Sam's ex-girlfriend Nikki leaves Grandview. Melinda revealed her gift to Jim/Sam in episode 4.16 "Ghost Busted" and his response was unexpected. Melinda told Jim/Sam he is really Jim in episode 4.17 "Delusions Of Grandview". Melinda saves Jim/Sam from drowning in episode 4.18 "Leap Of Faith" and is surprised when he asks her why she is calling him Sam. Melinda learned she was pregnant in episode 4.20 "Stage Fright" with Jim's baby. Melinda and Jim wed again in episode 4.23 "Book of Changes".
- Jennifer Love Hewitt as Melinda Gordon (23 episodes)
- David Conrad as Jim Clancy/Sam Lucas (23 episodes)
- Camryn Manheim as Delia Banks (23 episodes)
- Jay Mohr as Rick Payne (1 episode)
- Christoph Sanders as Ned Banks (13 episodes)
- Jamie Kennedy as Eli James (23 episodes)
- Big Chills
- Ghost in the Machine
- Save Our Souls
- Imaginary Friends and Enemies
- Heart and Soul
- Pieces of You
- Ball and Chain
- Life on the Line
- This Joint's Haunted
- Body of Water
- Slow Burn
- Greek Tragedy
- Ghost Busted
- Delusions of Grandview
- Leap of Faith
- Thrilled to Death
- Stage Fright
- Endless Love
- Book of Changes