"AGT: Fantasy League" may be a judge’s dream, but it’s turning into a nightmare for Simon Cowell.

Team Heidi contestant Hans delivered the sass with his vivacious musical number during the Monday series premiere of the “America’s Got Talent” spinoff. On “Fantasy League,” “AGT” judges Cowell, Howie Mandel, Heidi Klum and returning judge Mel B assemble all-star teams consisting of fan-favorite contestants across “Got Talent” franchises.

Hans, who placed as a quarter finalist on “AGT” Season 13, hammed it up for his return, playing Liberace’s piano and playfully gyrating for his cover of Elton John’s “The Bitch is Back.” The German musician capped off the performance with an accordion solo and a cheeky shoutout to his “frenemy” Cowell. “I know you love it Simon,” Hans said.

Hans charmed Mel B with his energetic stage presence. “My cheeks are hurting me because you bring so much joy to the stage,” she said.

However, Hans was unable to make a fan of Cowell, who said the performance wasn’t his “cup of tea.”

“If I’m being honest with you, he can’t sing, he can’t dance,” to which Hans shot back, “If I can’t sing and I can’t dance, when am I taking over your job, babe?”

The judges will compete among themselves throughout the season as they mentor and guide their acts to victory, which includes a prize of $250,000.

Mel B splashes Simon Cowell with drink after Spice Girls insult

Cowell learned the hard way that you don’t mess with Girl Power.

The British entertainment mogul poked fun at Mel B’s girl-group past during the performance of Team Mel B contestant Tape Face. The mime comedian, who was a finalist on “AGT” Season 11, made Cowell part of his zany variety show act.

Tape Face invited Cowell to stand onstage and place his hands on a microphone stand while the New Zealand comic blindfolded him. After Cowell was blindfolded, Tape Face played a game of cup-and-ball, which earned roaring applause when he successfully sunk the ball into the cup. A stunned Cowell, who didn’t witness Tape Face’s triumph, walked back to his seat in confusion.

“That was brilliant,” Mel B said. “You know why it was so good? We got to see you, and we got to see Simon just standing there looking pointless.”

But Cowell didn’t take Mel B’s jab in stride. “I stood there. I didn’t sing. I felt like a Spice Girl,” he said.

Mel B quickly got revenge by grabbing her drink and splashing Cowell with the beverage.

“So, unfortunately Mel won’t be joining us for the rest of the series,” he joked afterward.

Howie Mandel joins puppeteer Shadow Ace in ‘genius’ performance

Shadow Ace is pulling back the curtain on his dark act.

The shadow puppet artist, who placed as a semifinalist on “AGT” Season 18, enlisted the help of his mentor Mandel for his “Fantasy League” debut. Performing in view of the audience, the Filipino puppeteer entertained with the bodacious dances moves of his shadow-play characters, which grooved to the beat of hip-hop classics such as “Baby Got Back” by Sir Mix-A-Lot and Nelly’s “Hot in Herre” against a white backdrop lit by a spotlight.

Shadow Ace portrayed Mandel’s head as various props throughout the performance, including a turntable, a drum and a piano during a romantic pantomime of the Vanessa Carlton ballad “A Thousand Miles.”

“That was genius. Because weirdly, it made you realize how difficult this is,” Cowell said. “‘Cause sometimes you don’t want to see everything, but actually by seeing everything, it made it even funnier.”

Shadow Ace won over Mel B with his silly Mandel cameo.

“I could not stop laughing,” Mel B said. “You’ve brought me so much joy just bashing Howie’s head over and over. I loved it.”

Mel B steals Billy & Emily England from Simon Cowell with Golden Buzzer

With a Golden Buzzer in hand, all’s fair in love and war.

Team Simon duo Billy & Emily England floored the judges with its exhilarating roller-skating act, which saw Billy spin his sister Emily around at breakneck speed. The “AGT” Season 12 semifinalists upped the ante when Emily popped a series of balloons mid-air with flaming knives attached to her skates.

“Simon is very lucky to have you in his squad,” Mandel said. “This is one of the most dangerous, exciting stand-out acts we’ve ever had in ‘Got Talent’ history.”

But the Englands wouldn’t remain on Team Simon for very long. Mel B hit her Golden Buzzer button, which allowed her to steal the Las Vegas duo for her team and send them to the season finals.

“Honestly, when Simon called me (to be on the show), the 11-year-old Emily was a little bit upset,” Emily England revealed after the steal. “I really wanted to be part of Mel B’s team.”

Cowell was gutted by the blow to his “Fantasy League” dream team. “I actually feel like I’ve just been dumped,” he said.

Which ‘AGT: Fantasy League’ contestants made it to semifinals?

At the end of the night, host Terry Crews revealed which acts would be advancing to the semifinals round. Of the 10 contestants who performed, only five were voted through by the studio audience.

Up first was Team Howie’s V.Unbeatable, an acrobatic dance troupe that wowed with its high-flying flips and synchronized choreography.

Team Simon also scored a victory with singer-songwriter Kodi Lee, who melted hearts with his emotional performance of an original song.

Shadow Ace and sand artist Kseniya Simonova of Team Howie joined the winners’ circle on the strength of their captivating performances. And rounding out the top five was fellow Team Howie contestant Kristy Sellars, who dazzled with her graceful pole dancing number.

“Howie, you are on a streak,” Crews told Mandel.

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