'Avengers: Doomsday' drops fourth trailer, teasing a first-time meeting between two heroes

LOS ANGELES -- Marvel fans, assemble — another "Avengers: Doomsday" teaser has arrived, and it brings together two heroes who have never shared the screen before!

This latest glimpse marks the return of the Wakandans alongside the Talokans, led by Namor, who were introduced in "Black Panther: Wakanda Forever."

The teaser opens with Shuri's voice: "The King has his duties to prepare our people for the afterlife. I have mine."

She strides through the desert with purpose, joined by M'Baku, who soon encounters a very familiar, and very unexpected, face.

The moment ends with a humorous exchange.

"King M'Baku of Wakanda. Ben Yancy Street between Broome and Grand."

Ben Grimm, better known as The Thing from "The Fantastic Four," makes his debut in the trailer as well.

As with the previous three teasers, the clip closes on a countdown to the film's release date.

Speculation is already flooding the internet, and directors Joe and Anthony Russo are fueling the buzz. The duo posted a cryptic message on social media, urging fans to look closer.

"What you've been watching for the last four weeks ... are not teasers. Or trailers. They are stories. They are clues ... Pay attention."

So, what secrets are hiding in these recent teasers? And what exactly are the Russos trying to tell us?

One thing is for certain. "Avengers: Doomsday" releases in theaters Dec. 18.

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