Gemma Files was born in England and raised in Toronto, Canada. She has been a film critic, teacher, and screenwriter. Her 1999 International Horror Guild short fiction winner (and Aurora finalist) "The Emperor's Old Bones" appears in her collection The Worm in Every Heart (Prime, 2004). Both it and her earlier collection, Kissing Carrion (Prime, 2003) feature two stories that were adapted into episodes of The Hunger, an anthology TV show produced by Ridley and Tony Scott's Scot Free Productions. She has also published two chapbooks of poetry, Bent Under Night (Sinnersphere, 2004) and Dust Radio (Kelp Queen, 2007).

Her story "Spectral Evidence" won the 2006 ChiZine/Leisure Books short story contest. "Each thing I show you is a piece of my death" (co-written with her husband Stephen J. Barringer), appeared in Clockwork Phoenix 2 (Allen, ed.) and the 2nd Best Horror of the Year (Datlow, ed.), and was a 2009 Shirley Jackson novelette finalist. "The Jacaranda Smile," in the 2010 The Year's Best Dark Fantasy and Horror (Guran, ed.) was also a 2009 Jackson short story finalist. Other recent short fiction appears in Children of Old Leech (Lockhart and Steele, eds.), The Doll Project (Datlow, ed.), and Aghast Magazine. Her story "A Wish From A Bone," which appeared in Fearful Symmetries (Datlow, ed.), will be reprinted in Year's Best Dark Fantasy & Horror 2015 (Guran, ed.) and The Monstrous (Datlow, ed.). Her story "This Is Not For You," which originally appeared in Nightmare Magazine's Women Destroy Horror! Issue, will be reprinted in Best Horror of the Year Vol. 7 (Datlow, ed.).

Her first novel, A Book of Tongues: Volume One of the Hexslinger Series (ChiZine, 2010), was a Stoker first novel finalist and won a DarkScribe Magazine Black Quill award for "Best Small Press Chill" in both the Editor's and Readers' Choice categories. A Rope of Thorns (2011) and A Tree of Bones (2012) complete the trilogy. An Omnibus Edition including three new Hexverse short stories ("Hexmas," "Like A Bowl of Fire" and "In Scarlet Town (Today)") was released in December, 2013. Her next book, We Will All Go Down Together: Stories of the Five-Family Coven, a story-cycle of linked short fiction released in August of 2014. Her latest novel, Experimental Film, will be released in November,