The sister act ended on Monday night's "The Bachelor" as Ben Higgins decided to eliminate one of the sexy blonde twins who hoped to be his wife.

Week four of the show also featured aggressive Olivia doing a burlesque-style dance that fell embarrassingly flat and Ben inviting virgin Becca to a wedding chapel.    

When Ben and the gals visited Las Vegas on Monday's episode, twins Haley and Emily were thrilled because it's their hometown. Little did they know that heartbreak loomed.  

But first, JoJo got a one-on-one date with Ben. A gust of wind from the helicopter that would transport JoJo and Ben on their date sent a table practically falling on top of them. But they didn't miss a beat and immediately started making out with the other bachelorettes watching from the window.

"He's going to fall for her while I'm sitting in a hotel room," Olivia sobbed, losing her bravado. In the hotel suite, the girls selected for a group date included Olivia, which meant that Becca had won the second private date with Ben.  

Over dinner, JoJo told Ben she was cautious because her previous relationship had ended just five months before. But she assured Ben she was ready for love again; they kissed and he told the cameras he was falling for her.

Soon, Ben met the ladies for the group date, in which they would perform in a talent show as Vegas ventriloquist Terry Fator's opening act. Olivia picked out a sexy red sequined showgirl costume and promised Ben a surprise. 

After the other girls performed, Olivia jumped out of a prop white cake in a skimpy outfit and danced around awkwardly on stage. After some clumsy leg kicks, she went into the audience to flail around some more as Ben's face fell. Although Olivia didn't take off any clothes, Lauren B. summed up the feeling of the other women: "It was cringe-worthy."  

Olivia broke down in tears and said, "I'm having a panic attack" as she tried to run away from "The Bachelor" cameras.

"I don't have talents so I tried to do something way outside my comfort zone and it didn't go that well," Olivia cried in confessional.

Olivia was convinced Ben was mortified for her, lamenting backstage "I don't think I screamed marriage material."

At the cocktail party, Caila grabbed Ben and kissed him during their private time. A surprised Ben said shy Caila was "like a sex panther."

Later, Olivia approached Ben and sighed, "I did awful. What was I thinking?" Olivia told Ben she was embarrassed, but he said it wasn't bad.

While Ben talked to Emily, Olivia decided to get a second turn with him and interrupted them. After telling Ben she wanted to start over, he gave her a quick kiss.

The next day, Ben delivered a white wedding dress to Becca which left the other contestants confused.

"She's still a virgin," Jubilee snarked to the cameras about the woman who was Chris Soules' runner up on last season's "Bachelor."

Becca was taken to a wedding chapel where Ben got down on one knee and said, "Becca, will you marry ... other people with me today?" 

Ben had become an ordained minister and Becca was excited to help him out. Several couples came in and were married by Ben with Becca helping the brides with their vows.  

Later, at a neon museum in Vegas, Ben grilled Becca about whether she could fall in love—because she'd been standoffish with Soules. But she said she cared for Ben more.

He also brought up the elephant in the room: "You've chosen to be a virgin because of your faith," he said, adding that he was religious but hadn't waited to have sex. Becca admitted being a virgin was "really hard." Ben agreed it must be because with people you're attracted to, you want to "jump their bones," he said. Becca's virginity didn't seem to be an issue for Ben, as he raved in confessional, "She's perfect in every way."

The next day, Ben went out on a two-on-one date with Haley and Emily to determine which sister he would continue dating. They went to their mom's home where she told Ben that Emily was the more dominant twin.

Later, Ben sat down with the girls and said goodbye to Haley. Haley burst into tears but claimed to be happy that Emily would continue on the show. Emily also cried, but that didn't stop her from smooching Ben in the limo as she left her sister behind.

Later, Olivia interrupted Ben's chat with Jennifer and, after again discussing her dance disaster, confided to him, "I'm completely falling for you." Olivia told a doubtful JoJo she knew Ben reciprocated her feelings.

At the rose ceremony, Ben cut Amber and Rachel, giving roses to the other gals, including Olivia. Amber, who didn’t succeed on the last "Bachelor," either, walked away and cried in a lounge chair.

"The Bachelor" airs Mondays on ABC.