A former waitress is suing the high-end Japanese restaurant Megu for $20 million, saying it created a sexually hostile environment and ignored her pleas for help, according to legal papers filed yesterday.

A single mother of a 2-year-old, Satomi Southward, 31, joined Megu in TriBeCa in January 2005. It didn’t take more than a few months for the sexual harassment to start, she alleges in a verified complaint. Employees made sexually suggestive remarks to her and forcibly touched her with their hands and kitchen utensils, the complaints says. Senior restaurant employees did nothing when she complained about the harassment and abuse, the complaint says.

Ms. Southward alleges that at the annual Megu holiday party — described as a “raucous affair” with an open bar and hostesses hired to dress provocatively — a line chef, Herman Lawrence, drugged her drink, brought her to his car, and sexually abused her. When she returned to the party, a head chef tried to console her and escorted her back to her apartment, the complaint says. As they neared her door, he pressed himself upon her and forcibly kissed her, the complaint says.

Saying he was aroused “because you dressed sexy,” he told her: “Let me kiss you,” according to the complaint. She managed to push him away and close the door.

Then, Mr. Lawrence began calling her repeatedly at her apartment and she decided to report him to the police, the complaint says.

“The person that Ms. Southward has made criminal allegations against was promptly fired by Megu and has not been an employee since the alleged incident,” said James Goll, a spokesman for Food Scope America, which owns Megu. “That case is currently in the criminal court system and since it did not take place at Megu, or involve any Megu manager, Megu is not involved in the proceedings.”

Mr. Lawrence was arraigned on charges of sexual abuse in the first degree on April 19. He pleaded not guilty seven days later and was freed on $50,000 bail, according to the Manhattan district attorney’s office. He is also charged with sexual abuse in the first degree of another woman stemming from a July 14, 2005, incident.

“It was completely consensual,” the defense lawyer for Mr. Lawrence, Salvatore Pasynsky, said. “He denies all the allegations against him. Several witnesses at the party saw Ms. Southward flirting with Mr. Lawrence for quite some time. She willingly left the party.”

The abuse at the holiday party combined with the alleged sexual harassment at the restaurant led Ms. Southward to resign from Megu, the complaint says.

Ms. Southward received a letter from the president of Food Scope America, Hiro Nishida, questioning her allegations.

“Frankly, it seems odd that you would have continued to confide in” the head chef who allegedly pressed himself upon her “for months after the incident if he had done what you now claim, but perhaps your memory of the evening was clouded,” the letter said, according to the complaint. “But I hope you can appreciate that we have a responsibility to all our staff to operate the restaurant profitably.”

Mr. Nishida’s company owns 31 high-end restaurants in Japan in addition to two Megu restaurants in New York. A dinner at the restaurant costs about $150.