Batman: The Brave and the Bold
Bold Beginnings!
S3 E9:
After a team up with Space Ghost and his companions, Batman must come to the aid of three of his fellow superheroes who have fallen into the icy clutches of Mr. Freeze. As they wait to be rescued, Green Arrow, Plastic Man and Aquaman reminisce about their early crime-fighting days and how they first met the Caped Crusader.