The article provides a comparative analysis of the narrative structure of Mary Wollstonecraft Shelley’s Frankenstein: or, The Modern Prometheus and its rewrite – Theodore Roszak’s The Memoirs of Elizabeth Frankenstein. The ‟concentric” composition of Shelley’s novel, in which the three main narratives – Captain Walton’s, Victor Frankenstein’s and the Creature’s – were placed one inside the other, can be viewed as a variation on the popular gothic “found (discovered) manuscript” motif and were employed to enhance the emotional impact on the reader by blurring the line between fact and fiction. Roszak reproduces this structure in general, but bestows upon Walton (the primary narrator) an auctorial function, significantly expanding his “presence” in the main body of the text, represented by Elizabeth Frankenstein’s diary. While ultimately pursuing the same artistic objective as his literary predecessor, Roszak produces a more intricate system, in which each of the main characters has several functional roles; he also includes numerous inserted narratives in the text, thus complicating the structure in comparison with the elegant composition of Shelley’s novel, yet, however, meeting the same artistic goal more effectively: by intertwining fact and fiction, Roszak comes close to destroying the very fabric of the diegetic world and invading the extradiegetic reality of the reader and thus multiplies the emotional impact of the narrated events.