As we already know from WandaVision and The Falcon and The Winter Soldier, Marvel are not adverse to pulling in some unexpected characters from the MCU into their Disney+ series'. With only days to go until Loki premieres on the streaming service, head writer Michael Waldron has teased that fans should prepare for more of the same from the new series, only this time they should really plan on some cameos that they would never expect to see. Having already been told to "expect the unexpected", the question now is just who is going to put in an appearance in the time-travelling spin-off?

We have known for some time that of all the Marvel Series' landing this year, Loki was, appropriately, going to be the wildcard. WandaVision puzzled fans for a few episodes with its decade-spanning sitcom premise, which then fell away into an unfolding narrative. The Falcon and The Winter Soldier was always the obvious straight forward action spin-off, and there were very few people surprised to see Sam Wilson, aka The Falcon, take over Steve Rogers' mantle of Captain America.

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Both of these series' gave us new villains, Agatha in the former and US Agent in the latter, both of which now could potentially turn up any time in the future of the MCU. Essentially though, both series ended up being akin to Tolkien's appendices and additional books set around the events of The Lord of The Rings; they expanded on the stories of individual characters in an isolated way, it was enriching information but not essential if you only keep up with the movies.

Then we come to Loki. Ever since the 2012 version of Loki escaped with the Tesseract in Avengers: Endgame, it was clear that, despite the death of the "good" Loki at the beginning of Infinity War, there was now another Loki somewhere out there very much alive and a little megalomaniacal. Remember, this Loki is still very much a villain at this point, and still thinks Thanos is in charge. So, while we assume, that he is going to be told early on in the series what has transpired up to Endgame, we have to also believe that there will still be something of a villainous side to his character. Beyond that though, we know nothing. There has not been much given away by the trailers, the actors or the crew. With Waldron's comments we may know even less than we first thought.

Talking to DigitalSpy while on the Loki press tour, Waldron commented on the subject of cameos in the show, he said that there was virtually no character out of reach. "If they were within the rights, and legal could clear it, there was no reason we couldn't try and chase them down," he said. With the involvement of time-travel, and an expected crossover with other previous Marvel entries, this literally could lead to anyone appearing in the series. His comments also tie in with Kate Herron's interview with THR, when she said that Marvel chief Kevin Feige has told them to "go weirder" with Loki.

Waldron's comments are not he first he had made in relation to the "expect the unexpected" nature of the show. He previously said, "Because Tom is fun to watch, it is fun to write [a story on him]. Our first thought was to create a story about this character that hasn't been told in 10 years. Loki is an ass, and that makes my life as a writer easy. He's a man of frustration and chaos, and in any scene, anything can happen. This gives the writer a chance to take the story in different directions. Just like the shape-shifting character that Loki is, we wanted the show to be [unpredictable] as well."

We should bear in mind that Marvel have a habit of playing more tricks than Loki when it comes to setting up expectations. Who remembers the mostly fabricated Infinity War trailer? Or Paul Bettany's "actor he had always wanted to work with" comments about playing opposite himself? With some fans once again expecting their first sight of the elusive Mephisto, who is still believed to be coming as the next "big bad" of the series, this is a guessing game that is not going away in the next six weeks. With Loki having premiered last week on Disney+, we will likely start seeing these unexpected cameos pretty early on. In the meantime, let's play a game. Who do you think we will see making a fleeting appearance in the show? This news comes from ComicBook.com.