It's 1883—only a few months after Molly Pepper; her mother, Cassandra; and her friend, Emmett, saved New York from an attack by the megalomaniacal Ambrose Rector while managing to preserve the reputations of Alexander Graham Bell and Thomas Edison, whose technology was manipulated in Rector’s scheme. Their selfless heroism will finally earn them a place in the Inventors’ Guild, alongside the greatest minds of their generation. Unless, of course, no one knows that they did any of that.