Greer Grant persuaded scientist Joanne Tumulo to let her undergo experimental treatment as she did not trust the chosen test subject Malcolm Donalbain. When the treatment gave Grant enchanced physical and mental capabilities, Donalbain destroyed the lab with dynamite, resulted in Grant taking on the persona of "The Cat" to foil his scheme. Donalbain eventually committed suicide when The Cat wrecked his headquarters. Later, Grant learned that Tumulo was one of the few remaining members of a race known as the "Cat People" who were banished by sorcerers years ago, save for the first two. When Greer was fatally injured by HYDRA agents, Tumulo summoned a group of Cat People to perform a ritual to heal Greer and in the process, Greer was transformed into a humanoid tigress known as Tigra. Tigra gained the powers of an actual tiger from the transformation and continued her career as a heroine and eventually joined the Avengers.