Like any story about an art heist, this one starts with an empty space on the wall where fine artwork should be.

In this case, the wall was an expanse of rough pallet wood at Abyss Coffee in Ambler, the artwork a pair of 5-by-5-inch oil paintings by local artist Theresa Rooney, priced at a modest $125 apiece.

The paintings, part of a group show by the Artworks Collective, which Rooney manages, were hung on May 5, and went missing between May 10 and 12, disappearing from the wall one at a time, without a trace.

Abyss has posted “wanted” signs, offering an unspecified reward.

“People just can’t believe that it would happen in Ambler,” said Rooney, 53, who is actually a Blue Bell resident but counts herself an Amblerian. “It’s making everybody feel an icky feeling.”

Also like any whodunit, she said, there is a prime suspect: an individual who showed up that Friday on a street corner near the cafe, selling Mother’s Day flowers, and packed up on Sunday, not to be seen again. Though that is a practical time frame for Mother’s Day weekend flower sales, she supposed it just might also be true that, paintings purloined, the flower man was on the lam.

“A couple employees there said the guy came in a couple times and didn’t buy anything. They were just a little suspicious,” Rooney said.

She went to the Amber police on last Tuesday to report that the paintings were stolen. Detectives spoke to Abyss’ manager, who, police said, would check security video. But because of the way the camera is angled in the cafe, it wouldn’t show who plucked the paintings off the wall, said Amber Police Sgt. Thomas Craig.

A manager at Abyss could not be reached for comment Monday.

The art show, inspired by the Ambler Auto Show’s rumbling into town, took the theme “Planes, Trains and Automobiles" (though at least one rebellious participant submitted paintings of boats). Rooney included small paintings of five cars that held special meaning to her, on birch panels edged with silver leaf. The missing works featured a 1966 Mustang, a car Rooney and her sister had long obsessed over, and a ’78 Jeep that a friend had spent three years restoring.

For Rooney, the paintings are personal — and so is the theft, a blow to a burgeoning art scene she’s been working hard to cultivate.

All around town, people who’ve seen the reward notices have been coming up to her to express disbelief, she said. “People had a lot of questions about it.”

Staff writer Katie Park contributed to this article.