Paul Hayden was the obsessive, psychotic ex-boyfriend of Helen Bryce. He served as the main antagonist of the episode "Precipice" in the Second Season of Smallville.
Paul Hayden met Helen Bryce in medical school, but Helen broke up with him when his ex-girlfriend told her that he beat her up. Completely obsessed with Helen, Paul made it his life's journey to have Helen to himself. Paul visited Smallville and first saw Helen at the Talon. Helen saw him across the room, but when she looks back, he was gone. Paul then sent Helen her favorite flowers on her desk at the Smallville Medical Center. Paul then walked in and took credit for it surprising Helen and tells her he is in Smallville on business, and read that she was getting married to Lex Luthor. Lex walks in and Helen introduces Paul as a former boyfriend from med school. Lex has to break his lunch date with Helen. Paul offered to fill in, but Helen gets a call from a patient.
At the medical center, Helen Bryce finished for the day, but she can't start her car. Paul had sabotaged her car, and then showed up to rescue her. When Lex arrived, he accuses Paul of stalking Helen and suspects he tampered with the car. Paul went back to his hotel room muttering he'll do anything to be with Helen and then smashes his forehead into the mirror, injuring himself badly. Unknown to him, Lex had a security guard, Meacham, follow Paul. In the emergency room, Paul told Helen that Lex was responsible for his injuries. Helen confronts Lex about this accusation as the sheriff takes Paul's statement. Lex believed Paul must be unhinged to do that to himself.
Later Helen unexpectedly finds Paul in the pathology lab of the hospital. He tells her that he's been trying to make himself successful so she will take him back. But she rejects him telling Paul she loves Lex. When he tries to kiss her, she tries to run away, but he blocks her exit. Her phone rings and Paul lets her answer it. Helen tries to tip off Lex who senses something is wrong and rushes to her right away. Paul guessed that she was talking to Lex and beats her to within an inch of her life. Lex found Helen beaten and bloodied and became furious. Lex couldn't reach his security guard Meacham. Sheriff Adams had issued a warrant for Hayden's room at the Heartland Motel. Lex went to Paul's hotel room with Clark following. They heard a cellphone ring and find Meacham in the bathtub with his throat cut and realize that Hayden must be driving Meacham's car.
As the sheriff arrives, Lex grabs Meacham's gun and leaves with Clark. Lex uses the LoJack system to trace the car to a railway station. Lex spots Hayden in the crowd on the platform. Hayden runs behind the train, and Lex catches up with him between trains.