For more than 50 years, the Soviets employed an undercover agent --- an unstoppable, untraceable killer known as the Winter Soldier. His suspected identity? Bucky Barnes, Captain America's one-time partner, thought to have died in World War II. Now, the Winter Soldier is back, working for the ruthless General Lukin --- who has obtained a functional Cosmic Cube, a weapon of limitless power that can bend reality itself.