Christopher Plummer of Lyme, who federal authorities said portrayed himself as a managing member of a Wall Street investment firm and promised a 100 percent return on investments within two years, has pleaded guilty in U.S. District Court to conspiring to defraud investors of approximately $1.9 million.

The case of his former business partner and alleged co-conspirator, Maureen Clark, is pending. Plummer and Clark had operated the Lighthouse Inn, a landmark restaurant near the New London waterfront.

Plummer, 50, has been held in federal custody since he was arrested Nov. 29, 2010. He faces a maximum sentence of 20 years in prison when Judge Warren W. Eginton sentences him April 13 for conspiracy to commit wire fraud. He faces a fine of up to $250,000 and will be required to repay the victims of the scheme, according to the plea agreement he signed Thursday.

He has agreed to forfeit his interest in a 4.35-acre parcel of land in Stonington, an automobile and any funds that were seized during the investigation.

The plea agreement indicates the prosecutor, Assistant U.S. Attorney Michael S. McGarry, has calculated the prison sentence should be between 51 and 63 months under the federal guidelines. Defense attorney William Paetzoid asserts the sentencing range should be 33 to 41 months.

According to court documents, Plummer and Clark and others who have not been identified engaged in an investment scheme from 2006 to 2010, soliciting people to invest in a Lakeshore, Miss., development they said would include a casino, residential properties and a medical facility.

Plummer met with investors at the Lighthouse Inn and in Lyme, according to court documents. He and Clark sent emails to the investors claiming that major Wall Street investment firms had agreed to partner in the project and sold their investors "convertible term notes" that purported to pay 15 percent simple interest plus 5 points per year. The documents indicate that Plummer and Clark falsely represented to the investors that they owned hundreds of acres of land and options to purchase land in and around Lakeshore.

According to the government, Plummer also admitted to representing himself as a managing member of Madison and Wall Investments LLC and telling a victim he could invest his money with a firm that used a computer-based trading system and it would realize a 100 percent return within two years. The victim gave Plummer two $100,000 checks, which he deposited into a bank account in the name of Madison and Wall Investments and then wrote checks to himself, a co-conspirator and a mortgage company.

According to the plea agreement, Plummer sent an email to one investor in June 2007 that falsely stated that the "current take out situation with a major Wall Street firm will be a total buyout of the property of $1.5 billion, when in truth there was no such 'take out' plan."

Plummer and Clark are accused of diverting a significant portion of the fraudulently obtained money for their own personal use, including to pay expenses for the Lighthouse Inn and making mortgage payments on a property Plummer owned in Stonington. The New London business eventually was foreclosed.

k.florin@theday.com