Avengers: Endgame isn't even a week old, but already fans have started to pick apart nods, winks and references to the wider Marvel Universe featured in the film.
For as much as the fourth Avengers was about closing the book on the three previous phases of the MCU, it also had to set-up future movies along the way, whether that be in Thor joining the Guardians of the Galaxy, Sam Wilson becoming Captain America or by namedropping Captain Britain in a covert Easter egg.
The stage is set for a 'distinctly different' era of the franchise, and with the likes of The Eternals and Shang-Chi set to join the MCU in Phase Four, it's clear Marvel don't have a shortage of heroes to call upon to replace their departing stars. The acquisition of Fox and their partnership with Sony effectively means that no character is off limits, and with dozens of 'essential' heroes and villains still yet to feature in the films, it's understandable as to why each tease is met with excited chatter.
Endgame dangled plenty of future plot threads throughout its runtime, but one that may have coasted beneath the radar actually teases the arrival of a major Marvel hero - Namor the Sub-Mariner. But where does it happen? And why is all the fuss warranted? Let's dive in.