“American Idol” original judges Paula Abdul and Randy Jackson will...

“American Idol” original judges Paula Abdul and Randy Jackson will reunite onstage during Monday's episode on ABC. Above, from left, are "Idol" host Ryan Seacrest, current judge Lionel Richie, former judge Paula Abdul, current judge Katy Perry, former judge Randy Jackson and current judge Luke Bryan. Credit: ABC / Christopher Willard

Paula Abdul and Randy Jackson, two of the three original "American Idol" judges when the show launched in 2002, return for a reunion episode of the ABC singing competition Monday at 8 p.m.

"[W]e welcome back @PaulaAbdul, @YO_RANDYJACKSON & tons of iconic former Idols to celebrate 20 years of #AmericanIdol!" the show's Twitter account posted Saturday. Original judge Simon Cowell is not taking part in Monday's gathering.

The network added that popular "American Idol" alumni Lauren Alaina, Kris Allen, Laci Kaye Booth, David Cook, Laine Hardy, Caleb Lee Hutchinson, Grace Kinstler, Scotty McCreery, Maddie Poppe, Jordin Sparks, Willie Spence and Ruben Studdard also will appear along with "additional surprise guests."

Luke Bryan, Katy Perry and Lionel Richie are the current judges. This 20th season of the series, which ran on Fox through 2016 and was revived by ABC in 2018, features Patchogue's Christian Guardino in the top 10.

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