Joaquin Phoenix's Joker film may pay tribute to Jack Nicholson's Clown Prince of Crime.

In an Instagram post, IGDCEU points out that the background of a frame may contain a drawing of Nicholson's Joker from 1989's Batman. While it is not clear if it is actually an Easter egg, there does seem to be a resemblance, though only part of the artwork can be seen in the still below.

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While Nicholson's take on the character was iconic for its time, he was not the first to portray the Clown Prince of Crime on the big screen. That honor went to Cesar Romero in the 1966 film Batman: The Movie. Other actors who have portrayed Batman's arch nemesis include the late Heath Ledger, who won an Academy Award for his groundbreaking performance, and Jared Leto, whose Joker has been met with much criticism.

Directed by Todd Phillips, Joker stars Joaquin Phoenix, Robert De Niro, Zazie Beetz, Bill Camp, Frances Conroy, Brett Cullen, Glenn Fleshler, Douglas Hodge, Marc Maron, Josh Pais and Shea Whigham. The film arrives in theaters Oct. 4.

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