The Flash season 4's upcoming episode will provide some more details about its new villain, The Thinker and help set up The CW epic 4-show crossover event titled, Crisis On Earth-X.

Episode 7 titled, Therefore I Am, airing this Tuesday (21 November) at 8pm EST will find Barry coming face to face with the new villain, Clifford DeVoe aka The Thinker. The plot for the chapter also teases Barry and Iris' wedding plans, which will be the big plot for the crossover episode.

The official synopsis reads as follows:

Barry comes face to face with DeVoe; DeVoe's past is revealed; Iris puts the final touches on the wedding, only one week away.

In the promo for the episode, Barry is certain that Clifford Devoe is the villain that they are looking for, but the rest of the team is not convinced. Barry is seen saying in the promo, "This guy feels more dangerous than all the other combined," and then adds, "You don't believe me?"

The Star Labs team is not convinced and as he tells them, "I am telling you he is not what he seems. He's been watching us for weeks." Later he tries to explain to Iris, "This guy wants us t think I am assuming, but he is not."

"I don't understand why you don't see whats going on," says Barry hinting at some tension between Speedster and the other team members in the episode. The episode ends with Devoe cryptically saying, " I will be thinking of you."

Actor Grant Gustin spoke to Collider about the new villain and previewed the epic crossover event. Gustin teased that Devoe is three steps ahead of the Flash and explained, "The Thinker is more less about Barry and more about his vision of Central City and how he thinks he can make it better and make the world better. He doesn't really become obsessed with Barry and the team as in the way as they start to become."

"He's more all-knowing than any big bad we've had before. Every time we think we're ahead of him, we realize he's still three steps ahead," Gustin added about his adversary.

Speaking about the Arrowverse crossover event, Gustin said its "bigger than ever". He told the outlet, "It was bigger than ever. We knew it was going to be bigger than ever too. But every year, you can't really prepare yourself. You think you're preparing yourself, knowing that the crossover is coming but it's a big thing. It's a really challenging feat. I think this year, every year, we top it. "

"There's more people than ever included, some of the biggest sequences you'll see with the most superheroes we've ever seen together at any given time. But we stick also, at least The Flash side of things, we stick with the comedy we've had all year. That still exists within the crossover. Barry and Kara have a few interactions that are fun, and I meet a couple new characters. It's bigger than ever before," the Flash actor added.

Crisis on Earth-X
Superheroes unite to fight Nazis in The CW crossover event The CW/ screenshot