Jean Grey was offended by Cyclops' words during a training session that implies female heroes are too vulnerable than men. When she, Boom Boom, and Magma came upon a car chase, they intervened at Jean's suggestion and captured the criminals. Their actions inspired Jean in convincing the women X-Men to form a vigilante group dubbed as the Bayville Sirens. Their activities are held secret from the Xavier Institute.
The Sirens began raiding criminal operations, which most of them were run by the Kingpin. In response to the Sirens, the Kingpin hired Deadpool and Bullseye in guarding his latest weapons smuggling. The Sirens engaged the Kingpin's hired hands until it was interrupted by the arrival of Superman, Dazzler and Daredevil. The criminals were left at the hands of the authorities, but the Sirens were forced to disband at Superman's urging given that the Sirens were only founded by their personal reasons of needing respects and without consideration for the safety of their own lives.