Hough was one of the show's biggest pros, winning two of the five seasons she participated in. Later on, she returned to serve as a guest judge, and then became a full-time judge on the show for several seasons.
She's a beloved member of the DWTS family, so her return was a much-anticipated part of the two-part finale.
When she popped back onto viewers' screens for the first time all season, Twitter users went wild.
See some of the reactions below.
I’m way too excited about Julianne Hough being back on the show. Finally someone will make sense tonight. #Dwts— Erika (@erika89tc) November 21, 2017
juilanne hough is glowing tonight oh my lord— megs ♡ (@queerdaysgrace) November 21, 2017
Dancing With the Stars' season finale will air Tuesday at at 8 p.m. EST on ABC.