- —Kelsey Leigh[src]
Kelsey Leigh was a single mother with two young children who lived in Ipswich in East Anglia, England. She was a schoolteacher who taught English literature and history. Back when she was married, thugs invaded her home. One of them attempted to rape her: she fought back, hurting him somehow and he cut her face with a broken bottle in revenge, scarring her permanently. Meanwhile, her husband, Richard, was too paralyzed with fear to help her. His guilt over that incident led to the dissolution of their marriage.
Becoming Captain Britain
One fateful day, her family found themselves on the front line of a battle between the Avengers and the Wrecking Crew. Thunderball rendered Captain America unconscious and Kelsey selflessly put herself between the fallen Captain and Wasp, using the downed Captain's shield. While the shield was indestructible, Kelsey wasn't, and the shock from the blows inflicted terrible injuries on her; she died en route to receiving medical attention.
Kelsey awoke to find herself in a ring of standing stones, where she was met by a vision of Brian Braddock (the former Captain Britain), currently the ruler of Otherworld, and his wife, the elemental shapeshifter Meggan. To save Britain from the evil Morgan Le Fay, he passed the mantle of Captain Britain to Kelsey. Her heroic act of bravery earned her a second chance to live and to defend her home. Given the choice between the Sword of Might and the Amulet of Right, Kelsey, desperate to see her children again, and not seeing how a necklace could defend anything, chose the sword, the path of violence. Instantly, she was transformed into the new Captain Britain, only to discover that her decision meant that if she ever revealed who she was to her children, it would cost them their lives.
The new Captain Britain returned to Earth, where she helped the Avengers defeat Morgan and her cronies, proving herself to be far more ruthless in battle than her predecessor, and apparently killing Thunderball when she impaled him on her blade. With her children in the Avengers' care, Kelsey accepted an offer to join the team, so that even if she could not be reunited with her children, she could remain near them.
Kelsey remained a member of the Avengers until the events of Avengers Disassembled. When She-Hulk went berserk after an attack by Ultron robots, Kelsey stepped up, once again putting herself in the path of danger to rescue the fallen Captain America. She-Hulk knocked her unconscious, and she spent the remainder of the unfolding events in the hospital, her status critical. Kelsey did fully recover, but left the disbanding Avengers and returned home to England.
Soon afterward, the original Captain Britain returned to Earth and reclaimed the name. Going by the codename of Lionheart, Kelsey remained an active superhero in England but eventually came seeking revenge and blaming Captain Britain for what had happened to her, for not warning her of the consequences of choosing the Sword of Might and for losing her children.
Lionheart was manipulated by Albion, a supervillain who also dislikes Captain Britain. Lionheart, though struggling to fight her conscience, would have killed Courtney Ross, the Captain's former girlfriend, if it was not for the arrival of Juggernaut and Nocturne. After a fight between Albion and Captain Britain; Lionheart and Albion fled.
Later, Lionheart betrayed Albion, whose group was defeated by the New Excalibur team. It was then revealed by Pete Wisdom that when Kelsey died, she was "caught up in a rather sticky situation", but "the Crown needed her", and she had been on a "secret mission" since then. Because they felt it was safer to keep Kelsey's identity hidden from both her family and the public, for her family's safety, they waited until the end of the mission to reveal the truth to Kelsey's mother and children.
After taking on the mantle of Captain Britain, Lionheart possesses all the various superhuman attributes that go along with the title.
- Superhuman Strength: Lionheart possesses superhuman strength enabling her to lift approximately 90 tons.
- Superhuman Stamina: Lionheart's augmented musculature is much more efficient than that of a normal human. As a result, her muscles produce significantly fewer fatigue toxins during physical activity than those of ordinary humans. At her peak, she can exert herself physically for up to 24 hours before the build-up of fatigue toxins in her blood starts to impair her capabilities.
- Superhuman Agility: Lionheart's agility, balance, and bodily coordination are enhanced to levels that are beyond the natural physical limits of the finest human athlete.
- Superhuman Reflexes: Lionheart's reflexes are similarly enhanced and are superior to those possessed by the finest human athlete.
- Superhumanly Acute Senses: Lionheart's senses have been augmented to levels beyond that of ordinary humans, though their full limits remain unknown. She is able to see at much further distances than normal humans and retain perfect clarity when doing so. Her hearing is similarly enhanced, enabling her to detect sounds at greater distances. It is also possible that she can detect sounds that are too high pitched for normal humans to detect. It is unknown if her senses of touch, taste and smell are similarly augmented.
- Flight: Lionheart is able to propel herself at great speeds through the air, flying under her own power. At her peak, she is able to achieve a top speed of 770 miles per hour, which is roughly the speed of sound.
- Force Field: Lionheart is able to generate a protective force field around herself. Upon doing so, she gains great resistance to most forms of conventional physical injury. The field is sufficiently durable to withstand high caliber bullets, exposure to temperature extremes, and powerful energy blasts without penetration. She also generates the field typically while flying at very high speeds, protecting her from sustaining the various physical rigors and friction that flying at extreme velocities would cause.
- Destructive Blasts: Lionheart is able to generate mystical energy blasts from her Sword of Might, although it isn't clear how powerful the blasts are.
- Cosmetic Facial Alteration: Lionheart possesses a very noticeable scar on the left side of her face. While she isn't able to heal the scar, she is somehow able to remove the scar when she activates her powers. However, she usually chooses not to do so.
Lionheart has great knowledge of English history and literature, which were the subjects she taught as an educator. As a result of the training given to her by Albion, she is an excellent combatant. She has been extensively trained in various forms of martial arts and is an expert swordswoman.
- Sword of Might (formerly)
- Captain Britain's Uniform (formerly)
- Captain Britain's Quarterstaff (formerly)
- Quinjet (formerly), self powered flight
- 17 appearance(s) of Kelsey Leigh (Earth-616)
- 3 minor appearance(s) of Kelsey Leigh (Earth-616)
- 1 mention(s) of Kelsey Leigh (Earth-616)
- 16 image(s) of Kelsey Leigh (Earth-616)
- 3 quotation(s) by or about Kelsey Leigh (Earth-616)
- 1 item(s) used/owned by Kelsey Leigh (Earth-616)