EXCLUSIVE: Stephen Amell Reveals the Adorable Reason His Daughter Won't See 'TMNT 2' in Theaters

The 35-year-old actor also talks about his wife's 'super hardcore' Ninja Turtle fandom.

Arrow star Stephen Amell got to take on a completely foreign superhero world with his role as Casey Jones in Teenage Mutant Ninja Turtles: Out of the Shadows, and he took his 2-year-old daughter, Maverick, along for the ride.

"My daughter got to see the turtles' lair and the turtles' truck and stuff like that and that was really cool," Amell told ET's Carly Steel in a recent sitdown. "She was, like, one and a half so it was like a beat early, but she's getting fired up now. She saw her dress for the premiere this morning. She's getting excited."

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While little Mavi will be present at the premiere, she's still too young to see the movie. Amell told ET she'll probably go home after walking the red carpet.

"It's tough. I haven't done a lot of content yet that she's able to watch," Amell said. "She was able to watch Arrow when she was between six months and maybe a year and a half. Now she can't watch it for a while until I can explain to her that this is make believe."

In addition to the content of the movie, there's one more thing holding Mavi back from watching TMNT 2 on the big screen -- a fear of movie theaters.

WATCH: Stephen Amell Dishes on TMNT 2 and Olicity

"We went in there to watch the preview of Turtles when we were on the Warner Bros. lot back in L.A. and she was getting used to the theater, and then the lights went down and the sceen's so big and the sound is so crazy," Amell explained.

Mavi is Amell's first child with wife, actress Cassandra Jean, who happens to be a huge fan of the Turtles franchise. Amell shared that Jean joined him for a preliminary meeting that he had with director Dave Green in 2015 before Amell officially signed on.

"She asked one question, the director answered, and she goes, 'Is the character Casey Jones?'" Amell shared. "David Green has a terrible poker face so we found out. She was excited at that point for sure."

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As for his TV gig, Amell was thrilled about the massive Supergirl/Arrow/The Flash/DC's Legends of Tomorrow crossover The CW will be doing next season.

"I think if executed properly, it will be incredibly fun for the fans," he said.

Teenage Mutant Ninja Turtles: Out of the Shadows opens June 3.