The former office manager of a prominent New York orthopedic surgeon is suing him in federal court, alleging that the doctor had her followed by a private detective and arrested on false charges of grand larceny after she broke up with him.

The office manager, Susanne Schafmeister, accuses Dr. John Kennedy of "outrageous discriminatory, harassing and threatening behavior" in her lawsuit. She also accuses New York University Langone Health, where Kennedy leads the foot and ankle division, of improperly handling her allegations.

In a complaint filed Friday in Southern District criminal court in Manhattan, Schafmeister said she began dating Kennedy more than a decade ago, after she moved to New York from her native Germany.

Schafmeister later began working as the operations manager for Kennedy's private practice. Kennedy specialized in lower limb sports injuries and treated professional basketball, hockey and football players.

Earlier this year, NYU Langone Health announced that he'd been hired to lead its Foot and Ankle Center — a move that included Schafmeister, even though she'd broken up with Kennedy late last year, according to the lawsuit.

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The suit alleges that Kennedy's harassment and retaliation escalated after Schafmeister disclosed that she was dating someone else.

Kennedy allegedly demanded that she inventory and return all the gifts that he'd bought for her over the years.

When Schafmeister declined to inventory them but said they could be picked up by a third party, Kennedy allegedly sent her a message saying: "I am really baffled by why you want to go to war with me Susanne. I am not your enemy but if you continue to be adversarial I can behave that way also."

After Schafmeister filed a complaint with NYU Langone's human resources department about Kennedy in October, she learned that the doctor was "tracking her movements" through a private detective, the suit says.

The suit includes an alleged message from Kennedy to another doctor asking that an investigator be secretly alerted to Schafmeister's departure from the office.

Kennedy also allegedly told Schafmeister that he would report her to the "feds" for embezzling money from him — what the suit says were "concocted allegations."

Schafmeister says in the lawsuit that NYU Langone had offered her a bonus but later rescinded the offer. The suit says Kennedy instructed Schafmeister to cover the amount of the proposed bonus with a $12,000 check from his private practice.

A week later, Kennedy allegedly called her "screaming and laughing at her in a disturbing and erratic manner."

The suit alleges that the doctor pretended that Schafmeister had written the check without his consent and said: "Now I've got you. You have committed a felony."

On Nov. 18, Schafmeister was arrested and charged with second-degree grand larceny, according to the Manhattan district attorney's office. Kennedy also took out an order of protection against Schafmeister, a spokeswoman for the office said.

A complaint obtained by NBC News alleges that Schafmeister didn't have permission to write herself a $12,000 check dated July 17, 2019. The complaint also alleges that she embezzled more than $100,000 through more than a dozen other checks.

Schafmeister's suit denies that she wrote any checks without Kennedy's authorization.

The district attorney's office did not immediately respond to a request for comment about Schafmeister's lawsuit.

NYU Langone Health said in a statement: "We take seriously all internal allegations of inappropriate behavior and they have been and continue to be investigated. Likewise, we will defend the federal complaint in court at the appropriate time."

Schafmeister's attorney, Michael Willemin, said Schafmeister still works at NYU Langone Health, although she has been removed from the department and stripped of her responsibilities.

"Meanwhile, Dr. Kennedy still has all of his privileges to our knowledge," he said.