In Geoff Johns’ now-classic Flashpoint comic event, which rebooted the DC Universe into the New 52 back in 2011, The Flash travelled back in time to prevent the death of his mother and in the process created a new timeline. In this alternate DC Universe, Bruce Wayne was killed in Crime Alley. As a result, Thomas Wayne became a very vengeful Batman while Martha Wayne became The Joker.
That version of Batman has become extremely popular over the years and has returned to the comics a few times since Flashpoint, but now we may see him on the big screen. According to a report on The Cinema Spot, Jeffrey Dean Morgan may be returning to the DCEU to reprise his Batman V Superman role of Thomas Wayne in the upcoming Flash movie, which will be based on Flashpoint.
It’s only a rumor right now and there’s no confirmation yet, but given the popularity of the Thomas Wayne Batman, it’d make a lot of sense for them to bring him into live action when adapting the Flashpoint storyline to the big screen.