Keep a sharp eye out when watching Joker, or you may just miss a Batman: The Animated Series Easter egg.

In a post on Imgur, a photo appears to show Robert De Niro's Murray Franklin sitting at his talk show desk, with a sign reading "Live! with Murray Franklin" in the background. Batman fans may just recognize the lettering in the sign. Turns out, the lettering in "Live! with Murray Franklin" mimics the Andes font used for Batman: The Animated Series.

RELATED: Joker Director On Joaquin Phoenix Walking Out During Shooting - And Why

https://imgur.com/upxfPER

Since the Batman mythos has had a wide array of television shows and movies, this subtle Easter egg may not be the only reference to the Dark Knight's history in Todd Philip's Joker. Indeed, another fan seems to have spotted an Easter egg of Jack Nicholson's Joker from 1989's Batman.

RELATED: Joker Director Denies Reports DiCaprio Was Ever In the Running for the Role

As Joker's release looms closer, more reports are coming in regarding the film's development, including a debunked rumor that Leonardo DiCaprio was considered for the role of the iconic clown.

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.