The ghost of a childhood friend visits Lana, and she turns to Clark for help.

What's up with Lana? Lana is slowly warming up to Clark again, which he welcomes and Chloe jealously witnesses. After a spooky movie at the Talon, Lana sees what she thinks is the ghost of her childhood friend Emily. Clark comes in just as Lana tries to run from fright and the girl disappears. When he hears her ghost story, Clark suggest they visit Emily's dad. When they do, Mr. Dinsmore tells Lana he's never gotten over losing his daughter.

Who is Emily Dinsmore? Emily was Lana's friend who died by drowning after they both fell off the slippery bridge over the river where they played as children. What no one really knows is that Lana fell in the river, and Emily jumped in to rescue her. Lana was able to save herself but Emily drowned.

Later we see Emily talking to her father in the yard of their home. Her father tells her never to see Lana again. Emily throws a fit and disappears. A spike is "thrown" at the father, wounding him.

What's up with Chloe? Clark tells Chloe about Lana's "ghost" while he researches the little girl's death. Chloe thinks Lana's frightening apparitions could be psychological imaginings, due to the stress of the many sad experiences Lana has endured and still privately and tearfully tries to cope with. Chloe continues to grow exasperated by Clark's attention towards Lana. What's up with Lex? Lionel visits Lex to give him his wedding gift, since he doesn't expect an invitation. The gift is a Caribbean honeymoon on a private island. Why? Lionel tells Lex he just wants him to be happy.

Lex meets Emily in her father's hospital room. Lionel was at the hospital to visit Emily's father. Emily tells Lex that Lionel is a bad man, who took away all her pet bunnies from the backyard.

What's up with Clark? Clark and Pete visit the cemetery, finding Emily's grave. Using x-ray vision, Clark sees that her remains have been undisturbed. They see Emily. When she disappears, Clark realizes she has Clark's speed. He follows her, finding her locket as she runs away. Clark goes to the Talon to see Lana, and finds that Emily has just been there, again frightening Lana. Clark reassures Lana, saying he believes she saw Emily, as he did. He shows her the locket and explains that Emily cannot disappear like a ghost, but somehow moves faster than the eye can perceive.

At Emily's house, Clark and Lana find a hidden door behind Emily's bedroom wall. It leads to a basement lab where they find several clones of Emily. Lana spills some green liquid. By his weakness, Clark knows it is derived from kryptonite. Clark and Lana tell the Kents what they've found. The Sheriff investigates and finds nothing. When Clark returns to investigate, he finds the lab has been cleared, and discovers a confused Emily. When Lex arrives, Emily runs away. Lex finds Clark in the basement. Clark tells Lex LuthorCorp has been refining meteor rocks for cloning experiments. Lex admits he has met Emily and that Dinsmore had been working on accelerated growth experiments.

How it ends: From his hospital bed, Mr. Dinsmore tells Lex that chromosomal damage in Emily's clone makes her dangerous. Emily visits Lana again. She wants to go to the river to play. She runs off, with Lana chasing after her. Emily pushes Lana into the river. Clark arrives and jumps in to save Lana from drowning.

Lex confronts Lionel about the "Level 3" experiments and genetically engineering humans. Lex tells Lionel he has seen Emily. Lionel tells Lex he now has control of the Kawatche caves.

Lana visits Clark at the Kents to thank him for never doubting her, always believing in her. She fears that Clark sees her as perfect. She is not as good as he thinks she is, and she fears she will someday disappoint him. He reassures her. She holds his hands and says" Maybe its me that needs to start believing in you."

Lionel tells Mr. Dinsmore he no longer wants him on the project. Lionel calls Emily a defect, and the property of LuthorCorp. Mr. Dinsmore doesn't want to let her go. Lionel brings Emily a gift of a bunny. When Emily asks where her daddy is, Lionel tells her "Don't worry, I'm going to take very good care of you.".