Possible SPOILERS for Star Wars Rebels ahead!
In Rogue One: A Star Wars Story, there were plenty of Easter Eggs and references from Star Wars Rebels, the current animated series in the franchise, which takes place just a couple years before the film. But one was relegated to the film's supporting material and not mentioned in the actual dialogue of the movie, and it could have dire consequences for one of the supporting cast of Rebels.
POSSIBLE SPOILERS FROM HERE ON OUT!
In the book Star Wars Rogue One: The Ultimate Visual Guide by Star Wars Story Group's Pablo Hidalgo, there's more insight for every major character (and tons of side characters) in the movie, but Captain Cassian Andor's entry is the one that is spelling doom on Rebels - and a way we could see him again. In Andor's section, he has a list of "Operational Aliases" that include Willix, Aach, Joreth Sward (an Imperial agent alias!) and, most importantly, Fulcrum, noted as a "Recruitment agent in Albarrio sector."
In Star Wars Rebels, Fulcrum was a codename given first to Ahsoka Tano, who worked as a centerpoint (or fulcrum - get it?) connecting various groups of Rebels, and as a recruitment agent. When Ahsoka went missing, presumed dead, a new Fulcrum was named as Agent Kallus turned in secret and began feeding information and setting up others to turn to the Rebel Alliance. If Cassian Andor is a Fulcrum, that certainly seems like it means Kallus will either die or otherwise give up his post, and likely in the near future.
After all, Kallus is operating as a double agent while under the direct purview of the likes of Tarkin and Grand Admiral Thrawn. He will be found out, it's just a matter of when and whether the Rebel Alliance is able to extract him in time when it happens.
Cassian holding the role of Fulcrum doesn't mean Kallus is 100% doomed; it's been noted that there are more than one Fulcrum in play as the Rebel Alliance grows - especially since a specific sector is mentioned, and there's the above possibility that Kallus simply transitions out of the role. Perhaps most intriguing out of all of this is, if Cassian is one of the people with the title Fulcrum and the other two have been on Rebels, we could conceivably see Cassian make a stop on the animated series.
Rogue One: A Star Wars Story is in theaters now. Star Wars Rebels returns with all-new episodes January 7, 2017 on Disney XD, starting with a two-episode arc featuring Saw Gerrera, voiced by Rogue One actor Forest Whitaker.
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