Joey Lancianese’s flash mob proposal to Alex DeLoia takes over Pennsylvania street

This is one marriage proposal that you'll have to see to believe.

Originally planning to propose while on a Las Vegas family vacation over Labour Day weekend, 25-year-old Joey Lancianese, from Sewickley, Pennsylvania, had to change his plans after his girlfriend of six years, Alex DeLoia, started to get suspicious.

See more: Man proposes to girlfriend with cute flash mob while girl sits in car

Instead, Lancianese, who has a background in theatre, enlisted the help of Lenora Nemetz, a faculty member at the Broadway Dance Studio of Kennedy Township, and began to plan a flash mob featuring Bruno Mars' "Marry You."

"I'm a big believer that I want to do this one time and with the right person," Lancianese said before the big day that was two months in the making. "I want to make it as epic as possible."

The proposal truly was epic as DeLoia, who was lured to the corner of Beaver and Broad streets in Sewickley, with the promise of a dinner date with friends, wound up engaged by the end of the evening after witnessing a flash mob dance sequence dedicated to her.

See more: Band plays songs dedicated to wooing women

"They probably had about 150 to 175 people participating in this flash mob," Borough Manager Kevin Flannery, who helped Lancianese shut down the street for the proposal, said. "By the time it got started, there was a good 200-300 people here!"

Beginning with a single dancer grooving to Hall & Oates' 1981 single "You Make My Dreams" and then gradually growing to a crowd of dancers, including family and friends, as Mars' "Marry You" began to play, DeLoia seemed to be overcome with emotion watching the spectacle.

"It's a little understated, I understand," Lancianese said with a smile as he presented DeLoia with a diamond and rose gold engagement ring. "No idea is too big for us. We can do anything together. You are my best friend in the whole world, being with you has seriously been the happiest time of my entire life…Will you marry me?"

See more: Lady Gaga moved to tears by fans' flash mob video

"I'm completely speechless," DeLoia said after she accepted Lancianese's proposal. "I guess I wouldn't have expected anything less. I mean, I knew it wasn't going to be a restaurant proposal."

This isn't the first time "Marry You" has been used to pop the question. Check out Isaac Lamb's lip dub proposal to Amy Frenkel that occurred last May and relive the love by watching the video here.

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