The Book of Boba Fett trailer shows Boba Fett with eyebrows and fewer scars, which is a stark difference from his look in The Mandalorian season 2. In The Mandalorian season 2 finale's post-credits scene, Boba Fett and Fennec Shand arrived at Jabba the Hutt's palace on Tatooine and took control of the former gangster's dwindling empire, which appeared to have been trudging along since his death in Return of the Jedi - approximately 5-to-6 years prior to the events of the new Disney+ series.
Specific story details are being kept under wraps, but The Book of Boba Fett trailer strongly suggests Boba Fett and Fennec Shand will be working to reestablish connections in Star Wars' underworld, beginning with Jabba's former captains. As is to be expected, things won't come easy for Boba Fett; he will have to go to great lengths to ensure the security of his new empire in the criminal underworld, which will take time. Judging by the discoloring and battle scars on Boba Fett's armor, it seems there will be a time jump between The Mandalorian season 2 and The Book of Boba Fett.
Exactly when The Book of Boba Fett takes place in Star Wars' timeline remains to be seen, but it will surely be set not too long after The Mandalorian season 2. And it seems during that time, Boba Fett underwent treatment in a bacta tank provided he now has eyebrows and his facial scars have healed tremendously, both of which plagued him in The Mandalorian. A bacta tank first appeared in The Empire Strikes Back when the Rebel Alliance used one to treat Luke Skywalker's injuries after he was attacked by a wampa on Hoth.
Needless to say, Boba Fett's extensive scarring and injuries stemmed from years of bounty hunting and traversing the galaxy on his own, as well as surviving a sarlacc pit and subsequently living in the Tatooine desert for several years. It's not far-fetched to believe that he would've tried to restore his health in some meaningful way after he took over Jabba's palace. After all, Boba took time to repaint his Mandalorian armor in-between episodes of The Mandalorian, so he could certainly find the time to bathe in a bacta tank.
Bacta tanks offer impressive healing, after all. Darth Vader often used them while at his temple on Mustafar; presumably, being submerged in a bacta tank is the only place Anakin could survive outside of his Darth Vader armor. As for Boba Fett, he wouldn't need to be in bacta for too long; he could still handle himself quite well in The Mandalorian, and The Book of Boba Fett trailer shows that one element certainly hasn't changed.
The Book of Boba Fett premieres on December 29 on Disney+.
