- "If you'd like, I could rub [your hands] for you. Nothing heats up a body like friction. " - Sean to Chloe Sullivan, Cool
A stereotypical jock, Sean is a shameless womanizer known to always troll for "another notch" with teenage girls. Clark Kent describes him as "a total dog". Chloe Sullivan considers him "intellectually challenged but is really hot". Pete Ross thinks of him as "not that bad" and "always cool", but later jokingly refers to him as a "heat-sucking horndog". Even his football buddy Whitney Fordman considers his attitude towards girls as "cold".
Powers and Abilities
- Heat Absorption: After falling into a frozen, kryptonite-exposed lake, Sean Kelvin gained the ability to suck and or remove heat from all living beings including the Kryptonian Clark Kent. This usually killed humans, although Clark Kent quickly regained consciousness through his healing factor. He can turn both fire and water to ice by absorbing all the heat from them.
- Enhanced Strength: While nowhere near a solar-powered Kryptonian, after Sean was exposed to the kryptonite, his strength was enhanced, as witnessed when he broke through the ice that trapped him perior to his mutation, even though it became much thicker meanwhile.
- Oxygen Independency: After he was exposed to the kryptonite, Sean was underwater for a few hours and survived, showing the infection changed his physiology and canceled his need of oxygen.
- After his transformation, Sean's body had a dangerously low temperature, forcing him to drain body heat from others.
At a bonfire party beside Crater Lake, Sean tries to flirt with Chloe, who is unimpressed with his advance because his ex-girlfriend Jenna Barnum has already told Chloe about how Sean dumped her. Sean persists and gets Chloe's number, which Chloe gives him to get rid of him.
While playing catch with Whitney, Sean walks onto the frozen lake to retrieve the football and falls through the ice. With nobody seeing or hearing him, he gets trapped underwater in the lake, which is infested with green kryptonite. However he survives and manages to free himself the next morning, but his skin has turned blue with coldness. By reaching his shivering hand at a weakly bonfire, he absorbs the heat out of the fire and warms himself. At the hospital, Sean realizes that by stealing the body heat of others, he stays warm longer for at least a day.
Sean approaches Chloe to ask her out on a date, but abandons the conversation as soon as he sees his ex-girlfriend Jenna. Jenna falls for Sean's pretentious attempt to reconcile and brings him to her home. While she is having a shower, Sean surprises her and sucks out her body heat, rendering her into an ice statue as she crashes to the floor, shattered to pieces. Sean then tries to find a next victim by calling each of his ex-girlfriends to meet up, but gets rejected by all. He calls Chloe and offers a coffee chat, and Chloe agrees to meet him at the Torch office after school. Sean then lures Chloe into the school pool room, and traps her left foot with ice when she tries to escape by swimming across the pool. However, Clark has seen the news of Jenna's death and arrives to rescue Chloe. Sean flees after a brief scuffle with Clark.
Sean breaks into a local substation and strengthens himself by stealing electrical energy from the powerlines, causing a blackout across Smallville. He makes Whitney and Lana crash their truck, and ambushes Clark to absorb his body heat, but Clark manages to survive the freeze. Sean then sabotages the backup generator at the nearby Luthor Mansion and tries to drain the heat from Martha Kent, but a recovered Clark arrives to confront him. They fight and Clark manages to hurl him into a nearby pond. Unable to control his power, Sean sucks all the heat from the water around him, encasing himself in ice.
Chloe and Pete discovered a secret underground laboratory built by Dr. Donovan Jamison, Dr. Steven Hamilton and Dr. Arthur Walsh. The doctors were mining and using kryptonite to try and find a cure for meteor freaks. They had the bodies of several meteor freaks, including the frozen body of Sean Kelvin.
Sean was barely alive, encased in a block of ice. According to Dr. Jamison, Sean's heartbeats averaged around 50 a day. Jamison claimed to have plans to thaw him before proceeding to attempt to cure him of his mutation. Jamison later revealed that in his experiments he had extracted certain desirable properties from his subjects and put them into himself, including ice-related powers from Sean.
After Chloe and Pete caused an explosion and left the lab, they saw Sean's block of ice melting as they climbed out to safety. His current whereabouts are unknown, but it is unknown if he is alive.
- Season One: Cool
- Chloe Chronicles (Mentioned only)
- Season Three: Extinction (Mentioned only)
- Season Five: Fade (Mentioned only)
- Sean's profile name was shown in Vengeance Chronicles and Fade.
- The local news reported Sean as being 17 years old, which makes him a senior (same as Whitney Fordman) dating freshman girls.
- It is unknown if there were other victims of Sean's aside from Jenna Barnum, including his own parents who were not seen in this episode. If he did kill his parents he wouldn't have been the first meteor freak to do so, as Greg Arkin killed his own mother and Tina Greer killed her mother, Rose Greer.
- Sean's power is somewhat involuntary, as he automatically absorbed all the heat as soon as Clark hurled him into the pond.
- Kelvin (K) is the base unit for temperature used in the International System of Units (Système International d'unités, abbreviated as SI), with 0 K ( −273.15 °C or −459.67 °F) usually referred to as "absolute zero", thought to be the lowest possible temperature in the universe. Sean's last name is a reference to the power of coldness he gained.
- Sean's powers are the same of a villain in the comics, Killer Frost. Both were able to absorb heat and create ice, the only difference is that Frost could stay alive without absorbing heat while it was Sean's way of survival. Also Killer Frost was more experienced in using her powers creating blizzards and ice constructs while Sean was only capable of passively freezing things.