WARNING: The following contains spoilers for "Crisis on Infinite Earths, Part 2," which premiered Monday on The CW.
One of the most eagerly anticipated appearances in "Crisis on Infinite Earths" has been the arrival of Kingdom Come Superman, portrayed by longtime Arrowverse actor Brandon Routh in a direct nod to his starring role in 2006's Superman Returns.
The alternate universe Superman made his debut in the crossover event's second installment, with the mild-mannered Clark Kent appearing at the Daily Planet offices where he serves editor-in-chief. Approached by Earth-38's Clark and Lois Lane, along with Earth-1's Iris West-Allen, Routh's Superman is warned of the impending arrival of Lex Luthor, who's hunting Supermen across the Arrowverse.
Lois then notices a wall of memorial placards on the office walls, including this world's Lois, Jimmy Olsen and Perry White and asks what became of them. A heartbroken Superman reflects that, feeling he wasn't receiving enough coverage, The Joker gassed the offices, resulting in the death of his friends and wife.
As the group recruits the Kingdom Come Superman to join them, John Williams' familiar score begins to swell as Routh's Man of Steel suits up in an instant, immediately joined by Tyler Hoechlin's.
"Crisis on Infinite Earths" continues on 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.