Captain Cold
Alexander Petrov is a criminologist working for the Keystone City Police Department. But in order to advance his career, he uses one of Albert Desmond's weapons used as Mister Element to freeze the lab supervisor solid. Petrov is promoted to replace the dead supervisor and discovers he likes the thrill of killing. He continues to eliminate members of the department he sees as "threats" to his position, using the weapon and ice-based effects. He uses the effects and his position as head of the crime lab to shift suspicion to Captain Cold. His plan comes undone when profiler Ashley Zolomon enters his office as he is putting on his mask. The Flash is able to stop him from killing Zolomon, but Captain Cold interrupts them before the Flash can take him into custody. Captain Cold kills Petrov for breaking one of the rules of the Rogues' code of "ethics" - never frame another Rogue for your own crimes.