Harlem-born Carl Lucas, imprisoned for a crime he did not commit, agreed to undergo an experimental treatment designed to replicate the effects of the super soldier serum that created Captain America. As a result of the treatment, Carl's skin became unbreakable and his strength was increased to superhuman levels. Now bulletproof and capable of piercing through four centimeters of steel, Carl took the name Luke Cage and became a hero, working alongside his partner and friend Iron Fist to keep his streets safe.
Danny Rand was born into privilege, but his life was changed forever when his parents were killed by a family friend. Driven by a desire for revenge, Danny traveled to the mystical city of K'un-Lun. There he trained under Lei Kung the Thunderer, who transformed him into a living weapon. As a final test, Danny challenged and defeated the dragon Shou-Lao. When he plunged his fist into the dragon's molten heart, Danny became the wielder of the Iron Fist. After avenging his parents, Danny turned his life to serving others and became inseparable friends with Luke Cage as a Defender, Avenger and a Hero for Hire.