MIAMI —Investors claiming they were fleeced by a high-profile attorney filed a $100 million lawsuit Friday contending that the lawyer orchestrated a massive Ponzi scheme with the help of a Canadian bank’s U.S. subsidiary and several accomplices.

The 147-page lawsuit, filed in Broward County Circuit Court, in South Florida, alleges that attorney Scott Rothstein and others in his now-defunct firm used faked legal settlements — or faked their involvement in real cases — to promise fat returns for investors. TD Bank, the lawsuit claims, "was complicit in this scheme" by making the deals appear more legitimate and reassuring investors.