Secret Invasion: A Major Star From The Marvels Could Appear In The Finale
Contains spoilers for "Secret Invasion" Season 1, Episode 5 — "Harvest"
Nick Fury (Samuel L. Jackson) might want to fight Gravik (Kingsley Ben-Adir) alone even though his reason for not calling the Avengers only helps the Skrull, but he still seems to rely on a lot of people whenever possible. The former SHIELD bigshot might not have the resources he had back in the day, but he still has multiple allies around, and the mysterious phone call he makes at the end of Episode 5 might very well introduce yet another one.
At this point of the show, several of Fury's allies are either dead or replaced by a Skrull, and it seems that she's left both Varra (Charlayne Woodard) and G'iah (Emilia Clarke) behind for now. Since his sole remaining ally, Sonya Falsworth (Olivia Colman), is already with him, it seems that Fury is calling either Gravik ... or a hitherto unseen power player who will appear in the sixth and final episode. If we're looking at a newcomer, there's really one person who makes sense: Monica Rambeau (Teyonah Parris).
Monica and Fury have a history, as they already met in the 1990s during the events of "Captain Marvel." They're both used to somewhat shady superpower-themed missions, and we already know that they'll be working together in "The Marvels." As such, the Marvel Cinematic Universe will need to bring them together in some way — and what better way to do this than the phone call Fury makes?
Apart from Fury, Monica has a past with G'iah
It's worth noting that apart from Nick Fury, Monica Rambeau also knows G'iah. They met in "Captain Marvel" when they were kids and Fury and Carol Danvers (Brie Larson) were dealing with Talos (Ben Mendelsohn) once it turned out that the Skrulls in the movie aren't evil. Young Monica and G'iah seemed to hit off pretty well, which also speaks for Monica being a fitting character for "Secret Invasion." In fact, if the pair have remained friends over the years, the "Secret Invasion" finale could even set up a Fury-Talos-type dynamic between the two.
Monica also holds the distinction of being the sole "The Marvels" main character whom Fury can reach easily. They already know each other (unlike Fury and Iman Vellani's Kamala Khan) and Monica seems to be based on Earth (unlike Carol Danvers). What's more, she meets a seemingly friendly Skrull agent in the aftermath of "WandaVision," so presumably, Fury has already reached out to establish an alliance of some sort.
Since Monica isn't an Avenger, her assistance would technically allow Fury to maintain his Avengers-free Skrull-fighting code. Because she didn't receive her powers until after "Avengers: Endgame," she also wasn't subject to Fury's DNA-harvesting project. As such, she might be just about the only superhero out there whose help Fury is willing to ask, and who can hear the whole story without turning on her heels and leaving Fury to sort out his own mess. All in all, there are more than enough signs pointing toward Monica's potential appearance in the "Secret Invasion" finale. Whether this actually happens or not, we'll have to wait and see.