Supergirl Star Jon Cryer Teases Lex Luthor's Ultimate Endgame in Season 4 Finale

Supergirl and her allies will make one final attempt to stop Lex Luthor's evil plan in the Sunday night Season 4 finale of The CW's Supergirl, but when it comes to the full scope of the villain's plan it may end up being far worse than anyone expects. While Lex has set himself up as an American hero, his heroics are of his own orchestration, but according to actor Jon Cryer, the villain has something even more evil up his sleeve.

In recent interview with Entertainment Weekly, Cryer revealed that Lex's ultimate plan is "even darker" than he expected.

"[The finale] reveals his ultimate plan, which is even darker than I expected," Cryer said. "There's another plan within this plan. It reveals his more sociopathic tendencies, and that's actually what's been fun for me playing the character -- this iteration of Lex is a real threat. They really let Lex be scary."

Thus far this season has seen Lex manipulate his sister, Lena, (Katie McGrath) into curing him of cancer -- which in turn let him escape from prison. It also revealed that Lex gave himself that cancer as a way to procure Lena's Harun-El serum to stabilize the Kasnian Supergirl clone Red Daughter whom he had manipulated and twisted to be on his side as part of his even larger plan to have Kasnia attack the United States so he could in turn stop the invasion himself, killing Red Daughter -- as Supergirl -- in the process. That's pretty evil, but per Cryer, Lex goes even further.

"[His plan] also involves him getting revenge on Superman," Cryer said. "He really tries to wrap it all up in one super-duper evil plan."

Getting revenge on Superman, however, may have some major ramifications. As fans saw at the end of the "Elseworlds" crossover event, Superman (Tyler Hoechlin) is off Earth currently. He and Lois Lane (Elizabeth Tulloch) left for Argo after finding out that Lois is pregnant. As Superman doesn't have powers on Argo, it's a safer place for Lois to be while carrying their child. If Lex does try to get his revenge on Superman, it may mean that he's going to go after his family or, worse yet, even Argo entirely. It's that unknown element of Lex's master plan that could make Supergirl's mission to expose and stop Lex even more critical than even she could expect -- and could make for an explosive, high-stakes season finale.

Supergirl airs Sundays at 8 p.m. ET on The CW. The season finale, "The Quest For Peace", airs May 19.

What do you think Lex's ultimate evil plan is? Let us know in the comments below.