The offer came from an ex-boyfriend via text message: Come to Boston, Michael J. Shields Jr. allegedly told the woman, and I’ll get you a six-figure job at my tech company. A contract followed, then a lease for a $5,000-a-month Stuart Street apartment, then credit cards to pay for travel.

She quit her job in anticipation of the big move from upstate New York. But the illusion soon unraveled. There was no job, according to court records, and Shields was living in the rental himself — racking up a $76,000 credit card debt in the woman’s name as the scam progressed.

The allegations helped spark what is now a massive $350,000 fraud and larceny case against Shields, a New Hampshire resident, who faces dozens of counts involving at least seven victims. He pleaded not guilty Wednesday at his arraignment in Suffolk Superior Court.

Five of the victims were women with whom he had become romantically involved after meeting them online, prosecutors said.

He also allegedly bilked two people serving in the Army, collecting money from one for a stake in a company, but never investing it. Another childhood friend also allegedly agreed to let Shields open an account using his name as a way to build a credit history before reentering civilian life.

“Schemes like this one can have devastating financial consequences for the victims,’’ Suffolk District Attorney Daniel F. Conley said in a statement. “Putting aside the violation of their trust and the immediate financial loss, undoing the damage of credit card fraud can be a complex and time-consuming process.’’

Shields’s activities stretched from June 2015 to January 2016, Assistant Suffolk District Attorney George Barker said in court. Police said he didn’t even work at the company where he claimed to be offering the New York woman a $210,000-a-year job.

He had been charged in Boston Municipal Court last December in that case, and he is accused of attempting to intimidate her after he appeared in court on the matter.

“Try again! You failed I was released and your [sic] full of [expletive],’’ he wrote to her according to court records filed in that case.

Shields had his bail revoked on a separate identity theft case out of Woburn following that arrest. He was eventually found not guilty in the Woburn matter, according to court records.

As the Boston case continued, authorities filed several requests for information with financial companies as Boston police investigated.

By September, prosecutors wrote in a court document, they had uncovered evidence that the first case was “one incident of a widespread scheme by the defendant.’’

A grand jury returned a 45-count indictment Sept. 28, prosecutors said.

Barker said in court that Shields carried out the credit card schemes by offering to add them to his credit cards. Instead, prosecutors say, he used their information to open cards in their names, then spent large sums on vacations, clothes, meals, and jewelry.

In addition, Barker laid out incidents including one in which Shields allegedly used another woman’s debit card to borrow money, then passed bad checks to repay her. In another instance, he allegedly used a debit card that had been intercepted before its intended recipient ever got it.

Shields was ordered held on $7,500 bail after his arraignment Wednesday. Prosecutors had requested a bail of $20,000, but his lawyer argued that he would remain in the area to fight the allegations.

“He is well aware of the number and the nature and the size of the charges against him, and has come in on his own,’’ said defense attorney Andrew Stockwell-Alpert.

Shields returns to court Nov. 1.

Andy Rosen can be reached at andrew.rosen@globe.com. Follow him on Twitter at @andyrosen.