Avengers 4: 9 Surprise Cameos That Could Still Happen

5. Jane Foster

Although Jane Foster has only gone from strength to strength in the comics, having become the new Thor in light of the Odinson's unworthiness, the character didn't resonate all that well on the big screen.

Natalie Portman was a great pick to play Jane, who had yet to become the new Thor by the time the first film began production, but she was badly let down by poor writing and, by the time The Dark World came around, it was apparent to everyone that the character was nearing the exit door.

When Thor: Ragnarok scathingly removed the most forgettable aspects of the first two Thor movies, the Warriors Three and Jane were the first to go. Now, however, Jane could soon return - at least according to the Russos, who say that her fate post-snap classes as something of a "spoiler".

This surely means that she'll take part in the next Avengers. Maybe not as a major character, but in light of all the loss Thor's had to endure, bringing back Jane could yet mark a triumphant change of fortunes for him.