On Valentine’s Day, a vendor at a party convinces a heartbroken Lois to try on a lipstick that is laced with red kryptonite, promising her it will end her loneliness. After trying on the lipstick, it acts as an aphrodisiac, turning Lois into a love sick sexpot obsessed with the first man she looks at after putting it on. That man just happens to be Clark. Clark goes to Chloe to try and find a way to cure Lois, certain that she isn’t herself. Later, Lois kisses Clark, infecting him with red kryptonite. Like the previous times Clark has been exposed to red kryptonite, he loses his moral compass and acts freely. He has no problem using his special abilities in front of Lois, taking her in his arms for a short flight above the Metropolis skyline. Meanwhile, Lana asks Chloe to be her maid of honor. Chloe accepts.
So Chloe can attend Lex and Lana’s engagement dinner, Jimmy agrees to find a way to cure Lois. He pays a visit to a store in Metropolis that is owned by Star, the same vendor Lois bought the aphrodisiac from. Jimmy purchases a spray containing green kryptonite to reverse the effects the aphrodisiac had on Lois. Meanwhile, Clark and Lois crash the engagement dinner. Clark stirs up plenty of trouble by freely expressing his opinions on his family and friend’s relationships. He admits that he still has romantic feelings for Chloe, claims his mother has been acting more like a Luthor than a Kent since letting Lionel into her life, and breaks the news that Lana is pregnant. But that isn’t all. He also claims that the only reason Lana is marrying Lex is because of the pregnancy.
In an attempt to stop her from marrying Lex, Clark takes Lana to the Kent barn to propose to her. He insists Lana still has feelings for him. Lana doesn’t confirm or deny it, but also doesn’t resist sharing a kiss with him. Lex arrives just after the kiss. Clark tells Lex that Lana didn’t mind kissing him. Lex holds a gun to Clark when he won’t let the two leave the barn. Clark knocks the gun out of Lex’s hand, then starts to choke him. Lex is able to free himself by striking Clark in the chest with a chisel at the same time Martha enters the barn. Martha tells Lana and Lex that she will deal with Clark. As Lana helps Lex out of the barn, she notices that the chisel that Lex struck Clark with is bent as if it had hit a wall of steel. After the two are clearly out of sight, Martha uses a piece of green kryptonite to sweat the red kryptonite out of Clark’s system. When Lex confronts Lana about the kiss Clark and her shared, Lana turns the conversation in a different direction, asking Lex if he actually intended to use the gun he pulled on Clark to protect her or hurt Clark. Lex insists it was to protect her, though Lana has her doubts. After Lex leaves her room, Lana’s physician, Dr. Langston, informs him that everything is on schedule with her not so typical pregnancy.
In the end, Lois returns to her normal self, forgetting everything that happened during the time she was under the influence of red kryptonite. Martha tells Clark that even though red kryptonite changes the way he acts, the things he said under its influence were things he truly feels but has just been afraid to say out loud. She feels he needs to start being more honest and open about his feelings. Jimmy decides to break up with Chloe, feeling that she still has romantic feelings for Clark when she is quick to forgive and forget his recent rude behavior. Lana takes the bent chisel from the Kent barn and places it in a red cloth in a drawer in her room at the mansion.
Starring: Tom Welling (Clark Kent), Kristin Kreuk (Lana Lang), Michael Rosenbaum (Lex Luthor), Erica Durance (Lois Lane), Allison Mack (Chloe Sullivan), John Glover (Lionel Luthor), Annette O'Toole (Martha Kent)
Guest Starring: Aaron Ashmore (Jimmy Olsen), Simone Bailly (Star), Fred Henderson (Dr. Langston), Julie Brar (Dinner Guest #1), Noel Johansen (Dinner Guest #2), Judith Johnson Turner (Dinner Guest #3), Marshall Caplan (Dinner Guest #4), Allan Gray (Dinner Guest #5)
Written by Kelly Souders & Brian Peterson
Directed by Glen Winter