"The Devil's Own" was filmed on location and at the Chelsea Piers studios in New York City, as well as in Newark, Hoboken, Jersey City, Bayonne, Sandy Hook and Montclair, New Jersey. and Greenport, New York on Long Island. The opening scenes were filmed at Port Oriel, Clogherhead, County Louth, Republic of Ireland. The Belfast shootout scenes were filmed in Inchicore, Dublin in July 1996. Other location shoots in Ireland were in the Dublin Mountains. Two months before it opened, the film was still unfinished: Pakula was unhappy with the final scene ("a showdown on a boat with a cargo of Stinger missiles"), so in early February the scene was "rewritten and reshot over two days in a studio in California."