What if I were to tell you that Spider-Man had a very brief cameo in The Dark Knight? You’d think me crazy, I bet.

Well, according to an eagle-eyed viewer on Reddit, it seems this is indeed the case, as a Spider-Man 3 poster is seen in the distant background of a shot from the film.

It’s a real ‘blink, and you’ll miss it’ kind of shot, and even then, you’ll have to squint or have the expert enhancing equipment from CSI.

The poster is seen in the opening scene when Heath Ledger’s Joker conducts a bank heist, though its legitimacy is being questioned by other Redditors.

It takes a second user jumping in to show the scene in question and another blurry angle of the Spider-Man poster.

“Timetable lines up. Spidey 3 came out summer of 2007, right when they were shooting much of The Dark Knight in Chicago,” confirms another user, popavich.

It’s an interesting little detail to spot because you can be sure it’s unlikely we’d see this kind of thing nowadays.

As one user puts it, “Good guy DC is advertising Marvel movies in their film.”

Back then, when the war between Marvel and DC at the box office wasn’t so heated, and Disney didn’t own Marvel, this kind of thing happened a few times.

“And in the Raimi movies, Superman is a comic book character,” says another comic book fan.

“THEY ARE IN THE SAME UNIVERSE!” exclaims Hockataro with tongue in cheek.

Another lovely little comic book detail for the enthusiasts out there, though you have to wonder whether the crew just blanked on it being there or if it was just the done thing to rep another superhero film.

Of course, both films come from a time before the superhero rush in Hollywood and it’s good to see something so novel.