Although this was only the second "Lone Wolf" film produced by Columbia, Bert Lytell had already played Louis Joseph Vance's gentleman crook in several prior films, the first dating back to 1917. Michael Lanyard, aka the Lone Wolf, is sailing to America when he meets pretty Eve de Montalais (Lois Wilson). Eve wants to sneak her valuable necklace through U.S. customs so that she can use the money from its sale to help straighten out her brother. The only problem is that there is a gang of jewel thieves on board who are just as determined to steal the necklace.