He will co-star with Kate Lyn Sheil ("V/H/S," "House of Cards") in the indie mystery-drama about two long-distance online lovers who have never met in person.
Gallagher will play Cody, who, after suspecting that Virginia (Sheil) has been living in New York the entire time they have been in communication, sets out to investigate.
Gallagher's stage credits include Rabbit Hole, Spring Awakening, American Idiot and Jerusalem. His TV work includes "The Newsroom," "Law and Order: Special Victims Unit" and "The West Wing."
"The Heart Machine" is Wigon's debut film.