'Star Wars Rebels' is ending, but a major villain is back The Emperor returns in an exciting new trailer!

 -- Unfortunately for "Star Wars" fans, it’s time for “Rebels” to end.

The hit animated TV series is wrapping up its fourth and final season with six new episodes that begin airing Monday, Feb. 19, on DisneyXD. A two-part, 90-minute finale airs on March 5.

But before the show goes away, a classic "Star Wars" villain will make his first “Rebels” appearance: the evil Emperor Palpatine. In the new Rebels trailer released Friday, Palpatine comes face to face with one of the show’s lead heroes, a young Jedi named Ezra Bridger (Taylor Gray).

“Ezra Bridger, mine at last!” Palpatine hisses, as the two square off in a tornado of blue fire.

And if Palpatine’s voice sounds familiar, it is. He’s performed by Ian McDiarmid, the same Scottish actor who played him onscreen in both the original and prequel "Star Wars" trilogies.

“Rebels” began its run in 2014 with episodes introducing Bridger to a scrappy but dedicated team of rebels including Kanan (Freddie Prinze Jr.), Sabine (Tiya Sircar), Hera (Vanessa Marshall) and Zeb (Steve Blum), taking on the Galactic Empire from their home base, a ship called the Ghost.

In the "Star Wars" timeline, “Rebels” takes place after the events of “Episode III: Revenge of the Sith” and before “Episode IV: A New Hope.”

One question the new trailer does not answer is the fate of our heroes, especially fan-favorite Ahsoka Tano (Ashley Eckstein). The character first appeared in the 2008-2014 animated series “Star Wars: The Clone Wars." Back then, Ahsoka was a Jedi padawan under Anakin Skywalker before he went full dark side to become Darth Vader.

Ahsoka reappeared in “Rebels” but hasn’t been seen since the 2016 season two finale, following a duel with her former master inside a collapsing Sith temple. Darth makes it out alive. Ahsoka? Fans are not so sure.

At the "Star Wars" Celebration convention last April in Orlando, series creator and co-executive producer Dave Filoni trolled fans by wearing a t-shirt that cryptically changed from reading “Ahsoka Lives?” to “Ahsoka Lives!”

Whatever Ahsoka and the other rebel’s fate, Filoni says viewers need not be superfans to enjoy the show.

"If you started with 'Rebels,' you can watch the entire thing and never see any of the movies and still get the spirit of what 'Star Wars' is and how it all works," Filoni said in April.

That said, “Rebels” has had plenty of crossover with the live-action "Star Wars" films. Princess Leia, Yoda, Darth Vader, Lando Calrissian, Mon Mothma, Darth Maul, Obi Wan Kenobi, and even a very young Luke Skywalker are just some of the movie characters that have also appeared on “Rebels”.

And bits of “Rebels” have made the jump from TV to the big screen. In “Rogue One: A Star Wars Story”, eagle-eyed fans spotted the Ghost parked at the rebel base on Yavin 4 and flying through a climactic space battle. Chopper the droid is seen rolling through a hangar. And if you listen closely, a voice on a loudspeaker calls for Hera using her official title, “General Syndulla."

Filoni says that even though the Ghost crew gets a few nods in “Rogue One," they will get their own epic finale.

"I wouldn't like hanging this entire series we've done and my characters on something else we've already seen," Filoni told ABC News last year. "There would have to be something really epic that my guys are doing in that battle. And if there was something epic, it should've been in the movie."

The trailer also contains a few shots sure to spark plenty of fan speculation.

There’s the appearance of a mysterious owl-like bird known as a convor (or convoree in plural form, named after Filoni’s wife Anne Convery). They’ve been seen before, first in “The Clone Wars” but also right after the confrontation between Ahsoka and Vader in “Rebels."

Fan blogs like Spoiled Blue Milk suggest the convor might represent a powerful family of Force-wielders called The Ones, consisting of the Father, Son and Daughter. And indeed, another shot in the trailer features light emanating through what seems to be a giant hieroglyph of The Ones. If you don’t blink, you’ll see what appears to be a convor perched next to the Daughter.

Some fans have noted that the reference to Hera in “Rogue One” seems to ensure that no matter how bad things get in the final “Rebels” episodes, she survives.

As for the rest of the team? Difficult to see. Always in motion is the future.

"Star Wars Rebels" is produced by Lucasfilm, a division of ABC’s parent company, Disney.