Luca Guadagnino made accidental Spider-Man in-joke in Challengers

Luca Guadagnino didn't deliberately insert a 'Spider-Man' "in-joke" into 'Challengers'.

The director's new movie stars Zendaya as tennis prodigy Tashi Duncan, and a scene features the alter ego of the actress - who plays MJ opposite her real-life boyfriend Tom Holland in the superhero films - talking with her husband Art (Mike Faist) when they are interrupted by their daughter Lily, who asks if she can watch the 'Spider Man: Into the Spider-Verse' animated movie.

And while fans of the superhero saga were thrilled by the Easter egg, Luca admitted he didn't think about the tie to Zendaya when the line was written.

He explained to EW.com: “When you get rights for something to be used in a movie, it’s very complicated.

“Amy Pascal, our amazing producer, was of help there. I said, ‘Amy, can we use one of your catalog titles so it’s going to be easier to clear them?’ [Lily]’s a girl; she’s not going to choose to watch 'The Social Network' or 'The Post', but maybe she’s going to watch a 'Spider-Man' cartoon, so I said, ‘Why not 'Spider-Verse'?'

“Now I realise that it sounded like an in-joke, which, you know, the unconscious guides us all the time.”

Zendaya recently spoke of how much she enjoyed working with the 52-year-old filmmaker on the project.

She told Deadline: "Luca is brilliant. I think he has such a brilliant understanding about the human experience and deeply understands characters on another level.

"That was very apparent from the first time I spoke with him about this film and about these characters. He just knew who these people were in a deep sense and understood them, their hopes, their wants, their dreams, their desires, their fears.

"It was so special to be able to collaborate with him, work with him, and learn from him as well. We had tennis training and all these great things.

"But we also had rehearsal, which was something he had never done before, and it was just so special for us to have that time to work on the script, dig in, and get to know each other."