"My Girl" is the 11th episode of the first season of Superman: The Animated Series, and the 11th of the overall series. It depicts the return of Lana Lang, Clark Kent's High School Sweetheart. When Lana dates Lex Luthor and re-unites with Clark, she takes it upon herself to spy on Lex and tip off Superman to Lex's plans in spite of Superman's warnings.
A fashion show is being held in Metropolis and Clark and Lois are assigned to write up on it. As they watch the show, Lex Luthor shows up along with his newest date: Lana Lang. Clark is quite interested in the fact as he used to date Lana back in high school. While Lana leaves to work on her fashion show, Luthor meets up with an employee, Mr. Eelan, who speaks of some mysterious customers.
Lana finishes dressing up one of her girls and is soon confronted by two women who kidnap her to get her expensive dress. Clark walks in the room just after Lana's been taken. The kidnappers throw Lana into an elevator and are soon confronted by Superman. They toss Lana out of the elevator to distract Superman and attempt to escape. However, Superman manages to both save Lana and capture the criminals. After her rescue, Lana lets on that she knows that Superman is really Clark Kent. Luthor shows up after Superman leaves and expresses his happiness that showed up.
Later at Lana's apartment, Superman talks to Lana and asks how she was able to figure out his identity. Lana confesses that it was obvious as she saw him do those amazing skills back when they were in high school and noticed that both Superman and Clark Kent had arrived in Metropolis around the same time and easily made the connection. Superman then changes the subject and warns her about Luthor. He mentions that the man Luthor spoke to was an arms dealer and that he may be selling weapons for Luthor. Lana is unconcerned and assures him that she can handle Luthor. Superman then starts to leave, but again warns Lana to be careful. As he fies off away from Lana's apartment, he is seen by Mercy Graves.
Mercy reports what she saw to Luthor, but Lana manages to dissuade him from punishing her. Luthor speaks to his arms dealer, but Lana listens in on him. Mercy observes this and offers to kill Lana, but Luthor refuses. Outside, Lana calls up Clark and tells him about the arms deal.
Outside Metropolis, the arms dealer shows his customers a weapon that shoots a microwave beam and causes objects to overload their electrons and explode. Superman shows up and confronts them but only manages to capture the criminals. The arms dealer destroys a rail bridge and escapes while Superman saves the train.
Later that night in Metropolis park, Superman and Lana talk where Lana continues to insist that she becomes Superman's sidekick but he continues to refuse her. Lana then confesses that she still has feelings for him and asks to let her prove that they can be a great team. However, before Superman can further protest, Lana kisses him and they both share a moment. However, unbeknownst to either of them, Luthor is watching from afar and angrily leaves.
The next day, Lana has lunch with Luthor and overhears him talking to Eelan over the phone about another arms deal in Central City. Lana calls it in to Superman and still refuses to listen to his warnings. There's a knock at Lana's door and she enters into a limo only to find Eelan is driving.
Lana wakes up in a lead factory and is told that the because of the lead fumes the place is automated and Superman can't see them. She is placed in a mold for lead bars and is nearly covered in molten lead. However, Superman shows up anyway, revealing that he suspected Central City to be a ploy. Eelan attempts to stop Superman with his weapon and causes molten lead to fill the factory. Both Lana and Eelan are almost killed but Superman manages to save them both.
A few days later, Clark is reading the paper at the Daily Planet where Luthor is being investigated over the weapons he tried to sell. Lana then appears to him and informs him that she is heading off to Paris to continue her job while also informing him that she has learned her lesson after her ordeal. Clark reveals that he does indeed care about her even saying she is like a sister to him. Lana thanks Clark and tells him that he will find that special someone someday, however they are soon interrupted when Lois calls out to Clark informing him of a new assignment. Lana takes her leave and Clark heads to Lois.