Author of three books on post-World War II American literature, film, and culture: Fables of Fact: The New Journalism as New Fiction (Illinois, 1981), American Myth and the Legacy of Vietnam (Columbia, 1986), and The Kennedy Obsession: The American Myth of JFK (Columbia, 1997). His essays have appeared in such journals as American Quarterly, Genre, Critique, and American Literary History.

Hellman has been the recipient of a year-long grant from the American Council of Learned Societies (ACLS) and has been awarded Senior Fulbright Lectureships to teach in 1985 at the University of Antwerp (Belgium) and during 1992-93 at the University of Bonn (Germany). He has also taught as an invited lecturer at the University of Wales, Swansea. Most recently, Hellmann is the author of commissioned essays in the Cambridge Companion to Modern American Culture (2006), Edinburgh Companion to Twentieth-Century Literatures in English (2006), and The United States and the Legacy of the Vietnam War 1975-2005 (Palgrave, 2007). He is a member of the Interdisciplinary Film Studies Faculty at OSU, and is writing a book on Hitchcock's most important American films.