The trick is by no means sophisticated, but it tells the burglar if someone is home.
It was 9:30 on a quiet Belmont Street when an 86-year-old woman heard her doorbell.
"It was a split level house, and she was coming from an upper level and she walks with a walker, so it took her a while to get to the door," said Belmont Police Lt. Patrick Halleran.
When she finally got to the door, no one was there, but she heard a sound in the basement and went to check it out.
"When she opened the door to the stairwell, the burglar was standing at the top of the stairs. Both of them were surprised. She challenged him and asked him what he was doing in her house and the burglar fortunately turned ran back down the stairs and fled from the house," said Halleran.
Halleran says the doorbell was part of a ruse, one that's been used in the area in the past few months. The department even put out this you tube video of what it might look like.
"If you answer, they'll be offering gardening services or tell you they're lost or have some other legitimate sounding ploy for being in the neighborhood and obviously if you don't answer the door, then they go around back and force entry to your house," said Halleran.
Larry St. Lezin lives just down the street from where the break in happened. He says his next door neighbor's house was broken into just last summer. He and his wife were home and heard a noise.
"So we went over, he was coming down the driveway and said, 'I'm looking for my dog.' And we said, 'What are you doing in the back yard if you're looking for a dog?' And then he just took off and ran down the street," said Lezin.
Police want to hear from neighbors like St. Lezin, neighbors who notice when things aren't right and call police.
The man from this morning is Hispanic in his 30s, with a stocky build, 5'8" with a mustache and wearing a black jacket. Police think he may have gotten away quickly before they got here because he may have parked a car in an alleyway right behind the house.