Jon Favreau on 'Mandalorian' season 2's shocking finale cameo, 'Book of Boba Fett' details

Last week's surprise-filled season 2 finale of "The Mandalorian" ended with a Marvel-like post-credits scene that set up a previously unannounced "Star Wars" series for Disney+.

On Monday, "Mandalorian" creator Jon Favreau told "Good Morning America" a little more about that show, "The Book of Boba Fett."

As the title suggests, the series centers on Temuera Morrison's recently resurrected bounty hunter. The post-credits tease showed him taking the late Jabba the Hutt's throne for himself, with Ming-Na Wen's master assassin Fennec Shand by his side.

Favreau revealed the series is being worked on now and will air on Disney+ before season 3 of "The Mandalorian." He also revealed the logo for the new show, which reflects the color scheme of Fett's battle-scarred Mandalorian armor.

The "Lion King" director noted that he's personally working on that series as well as two others: "Ahsoka" and "Rangers of the New Republic" -- all of which take place during the timeline of "The Mandalorian."

Favreau also explained how nervous the cast and crew were about somebody spoiling the return of a certain Jedi in the finale's climax.

"It is very hard to keep a secret nowadays, especially with 'Star Wars,'" he added. "Every piece of casting [for this season] leaked. We were so scared right up until it aired, that our surprise cameo was gonna leak, too."

Mark Hamill reprised his role as Luke Skywalker in the show's breathtaking final minutes. The 69-year-old actor was on set for the top-secret scene and was later digitally de-aged to make him appear a few years older than he was in 1983's "Return of the Jedi."

"We started off the whole series with the Baby Yoda reveal ... that was a secret everyone was blown away by ... and then to have the very last episode, to have Mark Hamill," Favreau said.

“The fact that we were able to keep my involvement a secret for over a year with no leaks is nothing less than a miracle,” Hamill tweeted on Saturday. “A real triumph for spoiler-haters everywhere!”

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