During the Television Critics Association tour, it was announced that Wentworth Miller for a guest appearance as Leonard Snart aka Captain Cold.
Captain Cold has been one of the Flash’s most popular villains, especially with executive producer Geoff Johns, so it seems fitting that this leader of the Rogues would make an appearance during The Flash. Unfortunately, it seems like Snart will only be a one-time character as it is mentioned that this is only for a guest appearance.
Many of you might recognize Wentmorth Miller from the FOX show Prison Break in which he was the leading character.
The producers said we should expect to see Miller as Captain Cold during the fourth episode on The Flash.