The Flash: 24 WTF Moments

And now for the single biggest WTF moment in the entire movie - the cameo nobody could've even remotely seen coming.

In the film's final scene, Barry's life basically gets back to normal - his father is freed from prison, he sets a date with Iris West (Kiersey Clemons), and then sees Bruce Wayne pull up to the courthouse in a car.

Except, the Bruce Wayne who greets Barry? George freakin' Clooney.

Clooney seemingly finally has enough emotional distance from the failure of Batman and Robin to make an hilarious cameo as a very dapper-looking middle-aged Bruce, who seems rather amused that Barry doesn't recognise him, with Barry brashly asking, "Who the f**k is this?"

And to cap it off, Barry's glued tooth finally falls out of his mouth, before we smash-cut to the film's title.

The scene certainly asks some fascinating questions about precisely what's happened to Barry - has he now been banished to the Schumacherverse, or is there another explanation?

Though some excited fans are already theorising that Clooney could be the Batman of the imminent DCU, it's far more likely that this was just a fun gag to put a little bow on Clooney's DC tenure and give the movie a conversation-starter of an ending.