The listing, found here, confirms the product is 81.65 GB in size, runs on Xbox One, features multiplayer, and is rated M for Mature with "Intense Violence, Blood, [and] Language."
Modern Warfare best M4 builds: the best M4A1 loadouts we've found
In addition, the page contains one piece of artwork (seen above), alongside an official synopsis, which reads as follows:
"There is more than one truth. If you go looking for answers, be ready to question everything and accept that nothing will ever be the same. The Red Door awaits, do you dare step through it?"
As it happens, a listing for The Red Door was also found on the PlayStation Network a few weeks ago, alongside the content ID tag "COD2020INTALPHA1", suggesting this title is actually a front for the next Call of Duty game, rumoured to be named Call of Duty: Black Ops Cold War.
The next instalment in the long-running FPS series is rumoured to be in the works at Treyarch, and will softly reboot that studio's beloved Black Ops series. We've reached out to Activision for comment on this latest rumbling, and will let you know if we heard anything more.
For more, check out the best Call of Duty games in the series' history, or find out what we've been playing in this unusual times in the episode of Trending Topics below.