Actor Nicholas Cage recently opened up about his cameo appearance in The Flash. As a matter of surprise, he appears as an alternate version of Superman.

Speaking about his cameo, Cage said that he wished it was a longer one as was happy doing it. Speaking to USA Today, Cage said, "Well, I was glad I didn't blink. For me, it was the feeling of being actualised. Even that look for that particular character, finally seeing it on screen, was satisfying. But as I said, it's quick."

It may be noted that the actor was supposed to play the Man of Steel in Tim Bruton's canceled venture Superman Lives in 1998, following the success of Burton's Batman movies. 
 
Even though it is a brief appearance, Cage's Superman cameo is still significant, given that The Flash made room for a DC film that was scrapped in the long run. 

"I was supposed to play Clark Kent after that (in Superman Lives), and I was already developing this alien otherness playing this angel. That is a perfect example of the tonality you would've gotten for Kal-El and for Clark Kent: Clark would've been a little more amusing but Kal-El (had) the sensitivity and the goodness and the vulnerability and all those feelings that were kind of angelic and also terrifying."

Meanwhile, the fans appreciated that Cage finally got to portray Superman at least once.