In Thunderbolts #24 while CitizenV is going to shut down the device that's generating storms that the masters of evil created, she is knocked out. Who knocks her out is still a mystery at this time. Just as she is talking, someone says, "No, you're not." She responds with a "Hm? Someone." One 'Krac' on the head later and she is out of the picture. Suspects from knocking her unconscious include the masters of evil since it was there device, although they were all teleported away when this was happening. Slim change, but it could be Techno, due to the situation, and just the fact that it would be nice to see him again, and might be something he would do but why? Most likely someone no one really suspects or someone unknown.
As Citizen V was revealed to be Dallas Riordan in Thunderbolts #38 when she was already revealed to be the Crimson Cowl in Thunderbolts #25, it's not certain that Dallas ever was the Crimson Cowl. Its possible that she was knocked unconscious by someone and taken hostage by the Crimson Cowl and her Masters of evil. Then after the Masters of evil plan failed the Crimson Cowl made an escape and put Dallas into her Crimson Cowl costume to take the blame.
The Crimson Cowl captured Citizen V when she was interfering with the Crimson Cowl's plans. The Crimson Cowl used the cloak to teleport Dallas' body out of her uniform and into a non-functioning version of the Crimson Cowl's costume. The Crimson Cowl escaped while Dallas was revealed as the Crimson Cowl to the Thunderbolts.
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