Carmen Gonzalez was a child when she was kidnapped by Mexican scientists and sent to Russia. She was used for countless experiments, and turned into an assassin until they decided to close down the operation. Carmen was sent to be apart of a secret group called the Red Berets until she joins Las Vaqueros to capture El Sin Nombre. Valeria was given a choice to join the Las Vaqueros or be imprisoned which is how she eventually meets Carmen. Disclaimer: pictures and characters aren't mine besides Carmen and some side characters.
22 parts