By Jessica Dean
PHILADELPHIA (CBS) -- It's a trendy twist on the traditional wedding: throwing a regular party which turns into a surprise wedding. Sometimes the joke is on the guests. Sometimes it's a surprise to the bride or groom.
One party started as a retirement party for two police officers, Libby Watkins and Mike Conjura, until the flash mob showed up. A company called Flash Mob Weddings raced in to set up chairs, flowers, and a stage for a wedding –- a big surprise to the guests.
Lee Green had an even bigger plan when he proposed to his long-time girlfriend Amy last May: propose and get married on the same day.
"Very risky proposition!" Lee admitted.
Lee had secretly set up a surprise wedding at the Belmont Mansion in Philadelphia. Amy, who had always wanted to elope anyway, said yes.
"I felt almost like I would hyperventilate," Amy said. "Then I thought, of course this is how he would do it because that's him!"
It was picture perfect: More than 100 guests, flowers, a hair stylist.
As for the dress, Lee said, "I'd stolen a dress from her closet. I sent it to her mother, who is an excellent seamstress, and her mom made an absolutely lovely wedding dress."
The surprise trend is catching on with couples, says wedding expert Darcy Miller. "They decide that they don't want to go through all the months of all planning and all the details and the colors of the tablecloths, and they just want to get it done," Miller said.
Dwight Erickson spent three months planning a secret wedding. He even picked out nine dresses for his unsuspecting bride, Sandy.
"I would highly recommend it," Erickson said, "if you want to give your wife a stress-free wedding, and you know she's up for something like that."
Amy says she got the perfect wedding, a joyous celebration without worry. She's amazed Lee managed to keep it all secret for a year.
"I said to his mom, 'Wow! Your son's a really good liar!' She said, 'Yeah, aren't you glad?'"
Lee and Amy's wedding was photographed by JJ Tiziou Photography, who detailed the whole story here:
Mike and Libby's wedding was thrown by Flash Mob Weddings:
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