^And Cain was also in Smallville IIRC.
		
		
	 
Oh, that's right. He was the villain who was implicitly Vandal Savage.
	
	
		
		
			Shades also of how Flash has used various actors who appeared also in the 1990s version.
		
		
	 
Usually as the same characters! (More or less.)
Of course, it's an old tradition. There was a 
Lois and Clark episode where Jimmy Olsen was hyper-aged and turned into Jack Larson, Jimmy from the '50s 
Adventures of Superman. Larson also appeared in the syndicated 
Superboy series from the late '80s, IIRC. I think Kirk Alyn and Noel Neill played Lois's parents in the train scene in 
Superman: The Movie, and Phyllis Coates played Lois's mother in the first season of L&C (though she was replaced later by Beverly Garland). And 
Smallville also had Christopher Reeve and Margot Kidder. Then there's Adam West playing guest characters in multiple Batman cartoons, Kevin Conroy and Mark Hamill playing guest characters in 
The Batman and 
Batman: The Brave and the Bold, etc. And so on.