The first trailer for the Joker movie actually includes a brief glimpse of Bruce Wayne aka the future Batman - but it's easy to miss. Ahead of the release of Shazam! this weekend, Warner Bros. has dropped their first trailer for Joker, an origin story for the Clown Prince of Crime that's not tied to the DCEU in any way. Although the project was initially treated with some skepticism by moviegoers, director Todd Phillips has attracted an all-star cast including Joaquin Phoenix as Arthur Fleck, the man who will be come Joker.

The first Joker trailer has definitely whetted viewers' appetites. It has a strong, compelling narrative, really giving a sense of the kind of character Phoenix is attempting to play. The Joker costume is inspired by the classic 1960s Batman version, although there are visual nods to a lot of other incarnations too, and the trailer features a whole host of Easter eggs.

Related: Joker Trailer Breakdown: Story Reveals & Secrets

The most surprising of all, and the easiest to miss, is a brief appearance by the young Bruce Wayne. Yes, that Bruce Wayne. At one point in the trailer, Joker appears to stalk a child outside a wall then approach him at a barred gate, reaching through and forcing him to smile. That child is Dante Pereira-Olson, who has been cast as Bruce Wayne in Joker.

Joker Trailer - Young Bruce Wayne

While most indications are that Joker won't feature the Dark Knight himself, it's slowly becoming clear the Wayne family has a role to play. Thomas Wayne, played by Brett Cullen, is a key supporting player in the story, albeit very different to how most will know him. In the film, he's a mayoral candidate who, per casting reports, will be something of a Donald Trump-like character. This would suggest that he's being positioned as something approaching the antagonist, at least from Arthur's point of view.

It's been suggested that Arthur could actually be Thomas Wayne's illegitimate son. A key part of the transformation in Joker appears to hinge on Arthur's mother, who in character descriptions is said to be "'very attractive in her youth'", "'obsessed with her former employer'" and unable to believe 'this is what her life has come to'". This, along with Wayne's positioning, could point towards a big twist involving the character, making Joker actually Batman's half-brother.

Even if they're not linked by blood, clearly there's going to be some connection between Arthur and Bruce in Joker. This could merely be a foreshadowing of the pair's future showdown or a subversion of the Waynes' typical role, but that it's appeared in the first teaser - even without name confirmation - is very interesting and may be a hint to more. After all, why is Joker making Bruce Wayne smile?

Related: Jared Leto's Joker May Have a DCEU Future (Despite The New Movie)

In Tim Burton's Batman, the Joker was actually the one who killed the Waynes. It's possible Phillips will do the same in this film; Arthur watches Wayne condemn his reign of terror on TV, so there's certainly an obsessed motive a la Taxi Driver in there. In Burton's take, of course, the Joker was still Jack Napier at the point and didn't gain his permanent grin until Bruce was an adult; this would clearly move the event forward in the conventional timeline.

Whatever the case, clearly, there's a lot more going on with Batman in Joker than anyone thought.

More: All 31 Upcoming & In-Development DC Films

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