A mysterious flower named Nicodemus causes strange behavior in Smallville.

What's up with Jonathan? Jonathan is involved in an accident with James Beals, a LuthorCorp. employee who was speeding while talking on his cell phone. Beals was calling Lionel about a flower he stole from Dr. Hamilton's lab. After pulling Beals from the wreck, Jonathan gets sprayed by green pollen from the mysterious flower. Later at home, Jonathan has turned into a lazy slob, making rude comments to Lex, and shocking Clark and Martha with his uncharacteristic behavior. After being turned down for a loan, Jonathan goes to town with a shotgun for a confrontation. Clark tries to stop him and gets shot, just as Jonathan slips into unconsciousness. At the hospital, doctors tell Clark and Martha that Jonathan is suffering severe anaphylactic shock, like Beals who is now comatose.

What's up with Chloe? Trying to help the Kent's, Lana and Chloe search the scene of the accident for clues of exposure. Lana finds a flower and gets poofed with green pollen.

What's up with Lana? After exposure to the flower, Lana comes to school sexy and uninhibited. She breaks up with Whitney, then puts the moves on Clark. She leads him to the pool, strips down to her sexy red lace bra and panties, and dives into the water. Lana tempts Clark further with passionate kisses. All the flirtation knocks Clark off his feet and into the pool. At the Talon, Lana directs her flirtation towards Lex. He suspects something is up, as she grabs his car keys. Lana drives to the windmill. It has always been her deepest desire to climb to the top to see the skyline of Metropolis. Clark chases her there. Lana climbs up, passes out, and falls several stories into Clark's arms.

What's up with Martha? Clark arrives with paramedics bringing Lana to the hospital and learns that Jonathan has slipped into a coma and Beals has died. At constant vigil since Jonathan's admittance, Martha finally breaks down.

What's up with Lex? Lex traces the story of the Nicodemus plant back to when Smallville was almost wiped out as residents were exposed and died. Now Lex wants a flower from Dr. Hamilton's lab to send to Metropolis experts to find a cure. Dr. Hamilton is under Lex's employment to study meteor rocks. In his experiments, he had irradiated and germinated the flower's seeds, formerly dormant for more than 100 years. Clark suspects Lex's involvement when Chloe tells him that Lex had checked out a library book found in Dr. Hamilton's lab about the Nicodemus flower. Lex never confesses to Clark about his involvement with Dr. Hamilton's research.

What's up with Pete? When Chloe and Pete search Dr. Hamilton's lab, Pete is exposed to the flower. He threatens Chloe with a handgun found at the lab, and gets her car keys. Chloe tells Clark of Pete's violent behavior. Clark has just learned of Pete's jealousy of the friendship between Lex and Clark. Pete also holds a grudge against Lex because of LuthorCorp.'s dealings with his family's former business.

How it ends: Pete arrives at Luthor mansion as Lex is reviewing research notes for an antidote with Dr. Hamilton. Pete threatens Lex with the gun. He blames Lex for the illnesses. He blames him for deceiving Clark with false friendship while putting everyone in danger. Clark arrives and gets between Lex and Pete. Clark angrily denounces Lex, pushing him into the wall. He taps Pete on the head to knock him out. Clark helps Lex get up and Lex realizes it was just an act to control Pete and avoid a shooting.

Lex secretly closes Dr. Hamilton's lab in Smallville and moves him to his lab outside Metropolis to continue his meteor research.

What's up with Clark? Clark finally had his deepest desire fulfilled in Lana's passionate attention. But now that a Native American remedy has been found and all are recovered from the effects of the Nicodemus flower, Lana doesn't remember her flirtatious behavior, or that she had asked Clark if he loved her. Clark and Lana end the day sitting on top of the windmill, looking at the distant skyline of Metropolis together.