SPOILER ALERT: Do not read ahead if you have not watched the Season 9, episode 9 of “The Masked Singer,” which aired April 12 on Fox.

It was “Masked Singer in Space Night,” but “The Masked Singer” could have also been celebrating “’90s Night.” That’s because the two celebrities unmasked on Wednesday’s episodes were both TV stars from that era: Melissa Joan Hart (of “Clarissa Explains It All” and “Sabrina the Teenage Witch” fame) and Alicia Witt (“Cybill,” “Mr. Holland’s Opus”). Hart was revealed to be Lamp, while Witt was Dandelion.

Witt had won the previous week as Dandelion, but her journey ended here. For Dandelion, panelist Ken Jeong guessed Witt right. Jenny McCarthy Wahlberg thought it was Milla Jovovich. Robin Thicke went with Sara Bareilles and Nicole Scherzinger named Zooey Deschanel.

For Lamp, McCarthy Wahlberg, Thicke and Scherzinger all got it right with Hart. Jeong went rogue with Michelle Williams.

Like last season, “The Masked Singer” has once again adopted a “Champion of Masked Singer” format. Each episode, three costumed celebrities will perform, but only one will win and move on to compete again the following week. After each round, three finalists will compete in the semi-finals.

That means one contestant will be unmasked midway through the episode, with the top two singers facing off in a “battle royale.” After Witt as Dandelion was first to be unmasked, that left Lamp and UFO to face off with “Rocket Man” by Elton John. Lamp received fewer votes and was unmasked as Hart; UFO moves on.

New this season has “Ding Dong Keep It On.” In the new twist to the competition, panelists will have the opportunity to save a singer from looming elimination, but the bell can only be rung three times during the first three rounds. Those three singers will then face off on a special episode in a battle to rejoin the competition. Last week, the bell was rung for the last time, and Mantis was saved. The bell has now been retired for the rest of the season.

Melissa Joan Hart as Lamp and Alicia Witt as Dandelion join Dee Snider as the Doll, Christine Quinn as Scorpio, George Wendt as Moose, Holly Robinson Peete as Fairy, Alexa Bliss as Axolotl, Lele Pons as Jackalope, Malin Akerman as Squirrel, Michael Bolton as the Wolf, Grandmaster Flash as Polar Bear, Debbie Gibson as Night Owl, Howie Mandel as Rock Lobster, Sara Evans as Mustang and Dick Van Dyke as Gnome as the celebrities unmasked this season.

“The Masked Singer” enters Season 9 with 21 contestants include “Mustang,” “Axolotl,” “California Roll,” “Dandelion,” “Moose,” “Gargoyle,” “Jackalope,” “Doll,” Polar Bear,” “Night Owl,” “Rock Lobster,” “Gnome,” “Macaw,” “Squirrel,” “Wolf” and more to be announced. Tim Chappel is this season’s costume designer.

The Season 9 contestants “boast a combined 28 Emmy nominations, six Grammy wins, 10 gold albums, four Golden Globe nominations, five medals, 26 books, two Tony Award nominations, five Lifetime Achievement Awards, four stars on the Hollywood Walk of Fame and a combined 95,231,000 records sold.”  Season nine will introduce all-new themed episodes, including “ABBA Night,” “New York Night,” “DC Superheroes Night,” “Sesame Street Night,” “80s Night,” “Movie Night” and more.

Here were the contestants and their performances on night nine:

Lamp, “The Masked Singer” (Michael Becker/Fox) Pete Dadds


Song: “Venus,” by Bananarama

Panel guesses: Alyssa Milano, Neve Campbell, Jennifer Love Hewitt, Melissa Joan Hart, Tara Reid, Ali Larter

Clue: (Delivered by Daphne Zuniga): “Cover girl.” “Let me spell it out: MAXIM.”

Package voiceover: “Welcome aboard Masked Singer Airways. I’ll be your flight attendant, Lamp. And our final destination today is space. I’d like to start you all out with a warning that tonight’s flight might get a little bumpy. I’m terrified of singing, especially in front of people. But after navigating the silver skies as a pre-teen, I’m used to my fair share of turbulence. As if growing up in front of an audience wasn’t hard enough, I barely had time to myself to figure out who I actually was. But being a teen queen darling did come with a few first class perks, from Ryan Reynolds to Mario Lopez to James Van Der Beek. I’ve locked lips with some of my generation’s iconic heartthrobs. So buckle up and please return your seat to the full upright position as we prepare for landing.”

Previous song: “Don’t You (Forget About Me),” by Simple Minds

Previous panel guesses: Gene Simmons, Vince Lee, Tommy Lee, Donnie Wahlberg, Sebastian Bach

Dandelion, “The Masked Singer” (Michael Becker/Fox) Pete Dadds

Dandelion (ALICIA WITT)

Song: “Starlight,” by Muse

Panel guesses: Sara Bareilles, Milla Jovovich, Alicia Witt

Clue: (Delivered by Rovi the space rover): “Space Star.” “Are you ready for another spicy clue? The theme tonight is perfect for me, because I have plenty of experience with space.”

Package voiceover: “I had such a blast performing in this incredibly beautiful mask. Being on stage was nothing short of magic. But, there will be two new singers tonight who could get in the way. My challenge will be to connect with people through my music. Luckily, I have my beautiful dog to help me. He’s the only one who knows me by my voice. So I hope he doesn’t give away any secrets. I’m thrilled to go to outer space tonight. Space is meaningful to me because it showed me early what I wanted to do with the rest of my life. But it can get chilly in space, so here’s a clue that can make you feel all warm and cozy. [Santa hat with a laughing emoji.] Did that help?”

Previous song: “Over the Rainbow,” by Judy Garland

Previous panel guesses: Zooey Deschanel, Emmy Rossum, Reese Witherspoon

UFO, “The Masked Singer” (Michael Becker/Fox) Pete Dadds


Song: “Yellow,” by Coldplay

Panel guesses: Kendall Jenner, Gigi Hadid, Emily Blunt, Kaia Gerber

Clue: (Delivered by astronaut Mike Massimino): “Planet wide.” “I don’t like to brag, but I’m not just known in America but the whole galaxy.”

Package voiceover: “An unidentified flying object was spotted hovering over a runway in New England and moving west. The musical frequencies it’s emitting are influencing radio waves and masking local broadcasts across the country. Local reports in New York say it touched down on the runway for 30 seconds and struck a pose with the locals. Witnesses on the ground describe the object as ‘down to earth’ to begin with. Then it skyrocketed into the stratosphere overnight, along with several sister ships. Latest news show its course charted for the Masked Singer stage. Look out universe, this is no model plane. Prepare for possible invasion right now.”