In the Star Wars franchise, few bad guys are as good as Grand Admiral Thrawn. The military leader first introduced in literature is the Emperor’s true contender when it comes to displays of cunningness, but, while he is known to many, he is yet to make the jump to a live-action performance and thus a broader audience. If or when he does, there is plenty of material to work with and it shows a new side of the series, too.
For those unfamiliar, Thrawn first appeared in 1991 in writer Timothy Zahn’s trilogy of novels focusing on the character and what was the old expanded universe canon since declared to be “Legends” by Disney. He is a Chiss and was born Kivu’raw’nuru before he took the name Mitth’raw’nuruodo and the core name of Vurawn. He comes from the Unknown Regions of the Star Wars galaxy and, while the Chiss generally do not attack those who do not attack them first in different points of continuity, Thrawn generally disregards this. Such behavior led to Thrawn being exiled, though, in the new canon, his banishment is not what it appears to be.
According to the official Wookiepedia page for the character, he was given a false exile by his superiors in Chiss society in order to assess if the Galactic Empire was a threat or if it could be beneficial to their people. An encounter with some regular soldiers precedes a meeting with Emperor Palpatine directly, and, after convincing Palpatine there is a threat in the Unknown Regions and he will serve in exchange for the Empire’s help in dealing with it, Thrawn gets placed into the Imperial Navy’s training academy.
What follows is a number of adventures in comics and some short stories, and then the character gets re-canonized with an appearance on Star Wars Rebels beginning in 2016. Timothy Zahn was very pleased to see his creation come to digital life and the Lars Mikkelsen-voiced role menaced the heroes of the animated project until it ended in 2018. He is last seen disappearing into hyperspace with hero Ezra Bridger and since then he has been mentioned in The Mandalorian by former Jedi Ahsoka Tano. She appears to be looking for him and it is rumored the Ahsoka show in development could follow this with other Rebels heroes making an appearance too.
When it happens, expect Thrawn to be there in all his complexity, though, fans should not expect Mikkelsen to return. He had said in January, he has not yet received an offer, though if one did come his way he would likely accept it. But given all the attempts at secrecy that went into covering up the fact of Rosario Dawson playing Ahsoka Tano, the chances of Mikkelsen lying are also possible. Hopefully, the release of Ahsoka will put an end to these speculations once and for all.