The attacks have taken place on the streets in the city's River North neighborhood. One of the robberies happened outside Trump Tower. Police say the two suspects, a man and a woman, are targeting pedestrians who've been drinking.
On Tuesday, police showed ABC7 surveillance photos of the suspects in their vehicle, hunting for potential targets.
"They're driving around in this area, over and over and over again, until they can find the victim that they want to get," said Sgt. Edward Wodnicki, Chicago Police Department.
Police say all three robberies happened late at night in the busy River North entertainment district, where the guardian angels were handing out warning flyers to pedestrians on Tuesday.
"I think you just have to be aware," said Keenan Camp, who works in River North. "Maybe look forward a little bit more than you would instead of just staring at your feet while you're walking."
In all three incidents, police say the victims, two men and one woman, were alone and on foot and had been drinking late at night.
One robbery, involving an out-of-town visitor, happened near Trump Tower. The other two victims live in the neighborhood.
"Any time we've been drinking, our sense of situational awareness is reduced. And the bad guys know that," said Sgt. Wodnicki.
The suspects are described as a man and a woman. They were unarmed, but in two of the incidents, they roughed up the victims before stealing cash, jewelry, and other valuables.
"Just planning a little better, making sure you're on the main streets and not really near the alleyways. That's what I try to avoid as a traveler, as a visitor," said Meena Srinivasan, out-of-town visitor.
One of the robberies happened on Illinois Street between State and Wabash, the very same block where a bookstore employee last month was assaulted in the store at closing time.
At the Jazz Record Mart next door, employees aren't taking any chances.
"With us, we always leave in pairs. There's always at least two people closing, so that helps you know," said Chad Henderson, manager, Jazz Record Mart.
"Know where you're going. Remember where you're going. If you've been out, and you've had a bunch of drinks, it's easy to get lost downtown," said Sgt. Wodnicki.
None of the victims was seriously injured. The most recent of the three robberies happened last week. Police have only a vague description of the suspects, but again they were seen in that four-door vehicle, described as dark-colored.