On Saturday afternoon, the Faneuil Hall pub Ned Divine’s was buzzing with the chatter of young couples returning from a quest for romance and adventure—but more importantly, a diamond.

That morning, couples scavenged Boston to accrue points towards winning a $20,000, 2.4 karat diamond ring. Receiving clues on their cell phones, contestants completed tasks ranging from math problems to creating a football formation with unknowing bystanders. This so-called “Diamond Dash” was sponsored by Long’s Jewelers, a Massachusetts jewelry store.

For some, the Dash presented an opportunity to fulfill an engagement dream hindered by monetary constraints. For others, like winners Allison and Michael Harvey, it was a way to make a quick buck on their scavenging skills and knowledge of Boston. Contestant Bob Saphirstein said he wished to please his girlfriend who “likes shiny things.”

The Harvey duo—who are actually brother and sister—said they knew they had the ring in the bag. “We were the first ones back to the after-party location and the only people confident about our high scores,” said Allison. As other couples discussed lower point totals, the Harveys grew confident with their total 97 out of 104 possible points, she said.

As the announcements began, the Harveys gripped each others’ hands and a team called “The Karat Couple” hugged and squeezed their eyes shut. The event organizers suspensefully dialed the phone number of the winning team.

Allison’s phone buzzed. She screeched and ran onstage while Michael, pumping his fists in the air, followed. The crowd, displeased with the unromantic conclusion to the dash, booed when they learned of the siblings’ relationship. Although Michael claimed onstage that he would give the ring to his girlfriend, it seems this was to save face.

“We will probably sell it and split the money,” said Allison. “But I’ll wear it for now.”