With production on the upcoming CW crossover "Crisis on Infinite Earths" underway, images from the set have been leaking online. The newest one teases what actor Burt Ward will look like in his Arrowverse debut while hinting that he might appear alongside another hero.The image, which comes from YVRshoots, shows Ward walking a dog, with those commenting on the post speculating he might be Ace the Bat-Hound. If this is the case, it's unclear who Ward himself might be playing, as there are a number of options, though this would indicate he's playing someone associated with the Bat-family.RELATED: REPORT: Crisis on Infinite Earths May Involve a Major Batman Film's Universe

Ward is famous for playing Robin in the '60s Batman television series. In 1994, Ward co-founded Gentle Giants Rescue and Adoptions, an organization dedicated to helping dogs of all shapes and sizes, with his wife, Tracy. The organization even has an associated brand of dog food.

First appearing in 1955's Batman #92, Ace the Bat-Hound was created by Bill Finger and Sheldon Moldoff. Like the dog in the picture, Ace is a German Shepherd. His creation was inspired, in part, by Krypto the Superdog, who had appeared earlier that year.

"Crisis on Infinite Earths" begins Sunday, Dec. 8 at 8 p.m. ET/PT on Supergirl, then continues in Batwoman on Monday, Dec. 9 at 8 p.m. ET/PT and in The Flash on Tuesday, Dec. 10 at 8 p.m. ET/PT. After the winter hiatus, the crossover will conclude on Tuesday, Jan. 14 in Arrow at 8 p.m. ET/PT and in DC's Legends of Tomorrow at 9 p.m. ET/PT.

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