THREE ARMED ROBBERS didn't know what they were getting into Dec. 21 when they held up a South Philly hair salon and took jewelry from the owner, who happens to be the wife of a reputed mob figure, police say.

The Louisville, Ky., trio, visiting relatives in Darby for the holidays, went on a robbery spree for several days, knocking off businesses in South Philadelphia and Darby, cops said. They made a killing in spoils, which included the engagement and wedding rings of Terri Staino, 38, wife of reputed Philly mobster Anthony Staino.

Police say that the bandits would have gotten away with the crimes, and possibly more, if they hadn't been caught driving the wrong way on a one-way street an hour after they held up Staino at John Anthony Hair Styling for Men, at 10th and Tasker streets.

"It was a good job by the police," said Detective John Komorowski, of East Detectives, where the suspects were detained. "They were up here for a couple of days robbing, right before the holiday, but we recovered stolen belongings from two robberies."

"It was a horrible thing that happened to her," said Gregory Pagano, Terri Staino's attorney, when reached at his office yesterday. "She was an innocent victim."

Terri Staino declined to comment last night.

The episode began shortly after Staino arrived at her salon earlier than usual, about 9:15 a.m., police spokeswoman Christine O'Brien said.

She was alone inside and the door was still locked, when two men knocked on the door and asked to get haircuts, O'Brien said.

"She figured because of the holiday season they wanted haircuts, so she opens the door and offers them coffee," O'Brien said of Staino.

Staino went to the back of the salon, and one of the men followed. Pointing a gun at her face, he ordered her to take off her necklace, engagement ring and wedding ring, police said.

Meanwhile, an armed accomplice stole a laptop, Staino's checkbook and hair supplies before the men fled on foot, police said.

An hour later in North Philly, 24th District cops spotted a silver Honda with Kentucky tags going the wrong way on Water Street near Somerset, Komorowski said.

When police approached the car, they spotted a gun between the feet of the front passenger and arrested the three men, Komorowski said.

Investigators later realized that the trio fit the descriptions of suspects in the Staino robbery.

Later, cops searched the car and recovered four guns, Staino's stolen belongings and an item from another alleged robbery in South Philly two days earlier, Komorowski said.

The trio, who police identified as Tran Phuong, 36, Phuc Nguyen, 18, and Chau Tron, 21, face gun and robbery charges, as well as charges of recklessly endangering another person, criminal conspiracy, terroristic threats and other offenses.

Philadelphia Police and other law-enforcement agencies are looking into at least three other robberies that may involve the men, police said.

Anthony Staino, 55, is known to authorities as a longtime associate of the Ligambi crime organization. He's never been charged with a crime but is considered the No. 2 man in the South Philadelphia mob, according to news reports.

Anthony and Terri Staino - who, according to online records, have residences in South Philadelphia and Gloucester County - were married in September and reportedly had an extravagant wedding reception at the Curtis Center.

Among the 300 guests was Anthony's uncle, reputed Philadelphia mob figure Ralph "Junior" Staino Jr., 78.

Also on hand were Philadelphia cops and FBI agents, who snapped photos of guests as they arrived. Federal authorities subpoenaed the wedding photos.