When the Manhattan district attorney’s office charged four defendants Thursday with a combined 106 counts of criminal fraud, theft and conspiracy for allegedly concocting a scheme that put Dewey & LeBoeuf on the path to bankruptcy, three of the accused—the firm’s former chairman, Steven Davis; its former executive director, Stephen DiCarmine; and its former chief financial offer, Joel Sanders—were familiar figures to observers, and victims, of the Dewey debacle.

The fourth man named in the case was a stranger to even longtime Dewey insiders.

So who is Zachary Warren, the 29-year-old former client relations manager who prosecutors say “helped launch the scheme and helped cover up the fraud” that Davis, DiCarmine and Sanders allegedly continued until Dewey began to implode? (All four have pleaded not guilty to the charges against them.)