THE SOVIET SECRET ASSASSIN ON CASTLE'S TURF! Back when BUCKY BARNES was a mind-controlled sleeper agent, he was deployed for secret missions of political importance. But when he's unleashed in New York City, whose target will end up dead WINTER SOLDIER's or PUNISHER's? The Punisher's one-man war on the guilty crosses paths with other denizens of the Marvel Universe with explosive and unexpected results in THE PUNISHER SHOWDOWNS! RATED PARENTAL ADVISORY.