Fans aren't the only ones feeling nostalgic about the farewell season of American Idol.

The iconic series returns for its 15th and final season in January and ET caught up with original judges Paula Abdul and Randy Jackson to find out what they have planned for the milestone.

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"You'll see me there somewhere, yeah," Jackson teased at the All-Star Dog Rescue Celebration on Saturday. "[I'm] sad that it's ending but what a great run. 15 years! Oh my God! Whoa! The best ever!"

Abdul was similarly coy when asked at the same event whether she'd be back on the show this season. "I'm always last to find out if the rumors are true, but I'm sure I'll find out," she said. "I'm very grateful for the amazing time that I had. I was there for almost a decade when you think about it -- eight seasons, nine years. I'm just really proud to be a part of something that made history and changed the face of television as we know it today."

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Luckily, ET also was with Ryan Seacrest at Idol's Hollywood Week taping on Friday, where he offered up a bit more clarity on what we can expect from the show's alumni.

"We're going to have a lot of contestants coming back, the stars that were made from the show. We're also going to have the judges from the original series come back. We haven't figured out exactly what we're going to do but you'll see their faces," Seacrest confirmed. "I've seen [the judges] and spoken to them all since we put this together, so we're trying to figure out exactly how we're going to do it. But I'd say it's a team effort and I think that they realize that this is a special thing that's been a part of their lives forever."

Abdul and Jackson both echoed that sentiment, looking back on their first days on the series in 2002.

"It's so wild and I think, God, I've gotten a little bit more handsome in 15 years and I've grown a little bit more spiritual, a little bit wiser," Jackson teased.

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"I absolutely remember the first day of Idol," Abdul gushed, "and so does my sound man, who I met [again] recently -- probably a couple years ago. He said, 'I just want to introduce myself. I was your sound man on the first day of American Idol.'"

With a laugh, she recalled: "I go, 'Oh my gosh, I'm so sorry, I think I quit like three times.' He goes, 'No, eight!'"

You can see Abdul and Jackson on the All-Star Dog Rescue Celebration, hosted by Kaley Cuoco, airing on FOX on Thanksgiving Day.

The final season of Idol kicks off on January 6. Who are you hoping to see return to the show? Sound off in the comments section below!

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