In Honduras, two men in protective suits are making their way through the jungle as part of an evacuation. They find a hut containing several bloody corpses and start taking samples. An unprotected man enters – Professor Milton Fine. He rips off one man's protective suit and skewers the other one, then incinerates the hut with heat vision and departs at superspeed with the sample.
In Smallville, Clark and Lana are sharing a cup after a date but Clark bows out when the talk turns to intimacy. Lana assures him she'll wait and leaves, and a woman approaches Clark, introduces herself as Simone, and focuses on a necklace. It has an immediate effect on Clark, forcing him to obey her commands. They make out in the back alley but Lois shows up, interrupting them. Clark introduces Simone as his new girlfriend.
Lex is going over files on Honduras and information on Fine when Lana arrives. He tells her about Fine's disappearance and his connection to the ship's disappearance at the same name, and how Fine has been spotted in Honduras. He's heading to Honduras but wants Lana to stay behind. At the Kent farm, Clark demonstrates his superspeed, much to Simone's surprise and pleasure. At Chloe's dorm, Lois tells Chloe about what she saw but Chloe figures something is up and wants Lois to not tell Lana. Lana arrives and they cover up, then Lana gets a call from Clark who wants to talk to her.
Clark and Simone go up to the barn and Simone has Clark show her his other abilities. Afterward they strip and she asks Clark to make lover to her despite his concerns about injuring her. Before they can get too far, Lana walks in, leaves in shock, and Simone commands Clark to break it off. He confronts Lana who breaks into tears and leaves.
Simone arrives at Lex's manor and Lex talks to her by closed-circuit camera – he's aware of her mind-control abilities and that he sent her to break up Clark and Lana. Simone doesn't reveal what she knows of Clark's special abilities. Lex has evidence that can put her in prison and asks her to travel to Honduras. An underling tells Lex that they've found out Fine isn't who they think he is.
At the barn, Chloe talks to Clark and believes he's under some kind of influence, and isn't reassured by Clark's claim that he's in love. Chloe sneaks into the Kent house and runs into Simone, and lays on the praise to keep Simone unsuspicious, then takes her credit card from her purse when she isn't looking.
In Honduras, Lex arrives and Fine greets him – he's been laying a trail for Lex to follow. Lex reveals he knows what Fine is…a government operative working for a covert branch of the State department. It's another cover story and Fine lays on a story about how he's investigating the meteor shower and the ship that arrived with it.
At the Planet, Chloe tells Lois about her suspicion and has dug up information on how Simone's father was a doctor and hypnotist who died. He had the same necklace that Simone is now wearing. Lois offers to help but Chloe plans to do it herself to avoid giving away Clark's secret.
Fine takes Lex to village children, one who has a carving similar to the spaceship. The villager who saw the ship is dead, burned to death, and Fine warns that the race responsible poses a dire threat to Earth and they need LuthorCorp's help to develop a weapon.
Lois confronts Clark at the Kent house where he announces he and Simone are heading off to California. Clark knocks out Lois on Simone's command and when Martha shows up, Simone commands her to do whatever it takes to stop Lois from following them. Then she tells Clark she needs him to kill Lex.
Lois wakes up to find Martha pointing a shotgun at her and Chloe arrives to knock her out from behind then heads for the manor. Lex arrives at the manor to find Clark waiting for him. Clark tosses him around and Simone tells Clark to make Lex suffer. Clark starts to choke her but Chloe arrives with a piece of green kryptonite and puts it in Clark's pocket. Lex goes for a gun but Simone uses her necklace to order him to kill Chloe then himself. In the struggle the gun goes off, shattering the necklace and killing Simone. Chloe removes the green kryptonite and tosses it away before Lex notices.
Clark and Chloe meet at the Planet and Clark admits he's relieved that he broke up with Lana – her feelings were real and he's sick of lying to her. Chloe warns him to consider. Later at the barn, Lana arrives and Clark says his feelings have changed and he doesn't love her. An upset Lana says it's over…forever.
In Honduras, Fine in his liquid-metal form appears before the spaceship…along with several clones. He announces they need more samples and they take off into the jungle. Clark talks to Martha about the break-up and she suggest Clark broke up because deep down he didn't think she was the one, and that Clark not only broke up with her but angered her. Martha wonders if they might regret that…and at Lex's manor, Lana arrives and announces the break-up. Lex reassures her and is clearly intrigued by the news.