She was born in Woburn, Massachusetts May 11, 1966 and grew up in nearby Arlington, Massachusetts.
Intending to study Political Science, McCarthy initially attended Catholic University in Washington, D.C. but subsequently left to pursue other interests. She eventually enrolled at New York University where she earned a B.F.A. in Photography & Imaging from the Tisch School of the Arts, Maurice Kanbar Institute of Film & Television.
McCarthy held an administrative job in the early years of the MIT Media Lab, where she learned about computers. "I was exposed to the most bleeding-edge technology and everybody in that environment had a point of view to add, whether you were a tenured professor, or, like me, a glorified secretary -- it was all part of the mix. That was my first exposure to a barrier-free environment." This experience led her to the MIT Community Players which was her first exposure to the idea of theater as a potential career. After that she worked with an experimental theater company, the Pilgrim Theater Research and Performance Collaborative. While stage managing for them at the Edinburgh Festival it became clear to her that she wished to pursue a career in theater. She eventually worked her way to New York City working as a design assistant to noted projection designer Wendall K. Harrington through whose studio many of today's top projection design practitioners have passed. This is where she saw her varied interests in technology, art, design, photography, architecture, film and theater come together in one discipline, projection design for theater."
She has since gone on to work with a diverse group of notable directors including Leonard Foglia, Michael Greif, Kristin Hanggi, Andrei Konchalovsky, James Lapine, Joe Mantello, Michael Mayer, Dejan Miladinovi?, Mike Nichols, Jack O'Brien, Diane Paulus, Tim Robbins, Peter Sellars, Julie Taymor and John Tillinger.
She has many Broadway productions to her credit including After the Fall (2004 revival), Good Vibrations, The Green Bird, Judgement at Nuremberg, the Tony Award nominated productions of Man Of La Mancha (2002 Revival)  and Wicked, as well as the Tony Award winning productions of Into The Woods (2002 Revival), Assassins and Monty Python's Spamalot.
She designed projections for Tan Dun's adaptation of The Peony Pavilion at the Wiener Festwochen as well as Tchaikovsky´s Mazeppa  and the Andrei Konchalovsky directed production of Prokofiev's War and Peace, both co-productions of the Kirov Opera at the Mariinsky Theater in Saint Petersburg and the Metropolitan Opera in New York City. She recently designed Alfredo Catalani's La Wally and Tchaikovsky's rarely performed Iolanta for The Dallas Opera.
In the Fall of 2015 McCarthy returned to the Dallas Opera to design projections for the world premier production of Great Scott, a new opera by Jake Heggie and Terrance McNally directed by Jack O'Brien with Sets and Costumes by Bob Crowley and Lighting by Brian MacDevitt .
McCarthy designed projections for the world premiere of Jake Heggie's new opera It's a Wonderful Life for the Houston Grand Opera December 2016. The production was directed by Leonard Foglia with Sets by Robert Brill, Lighting by Brian Nason and Costumes by David C. Woolard.
Late summer 2016 McCarthy designed projections for the New England premier production of Notes from the Field: Doing Time in Education, created, written and performed by Anna Deavere Smith in Boston at the American Repertory Theater (A.R.T.) then it moved to New York City's Second Stage Theater that fall. Directed by Leonard Foglia with Set design by Riccardo Hernandez, costume design by Ann Hould-Ward, lighting design by Howell Binkley
Fall 2018 McCarthy designed projections for Gloria: A Life, the story of Gloria Steinem at the Daryl Roth Theatre starring Christine Lahti in the title role. It is written by Email Mann and directed by Diane Paulus with scenic design by Amy Rubin, costume design by Jessica Jahn, lighting design by Jeanette Yew and sound design by Leah Gelpe.
McCarthy is a frequent collaborator with Director Leonard Foglia. She designed projections for his Off-Broadway production The Stendhal Syndrome; his Broadway productions Thurgood, and The People in the Picture; and his production of the Opera's Dead Man Walking for the New York City Opera as well as the World Premiere productions of Moby-Dick  and Everest for the Dallas Opera and El Pasado Nunca se Termina for the Lyric Opera of Chicago for which she designed both Sets and Projections. "What Elaine is able to do," he says, "is to use my ideas as a departure for her own creativity. She will take my ideas and lift it out to a level I could never have imagined. It's what I pray every designer will do."
McCarthy was formerly an Adjunct Instructor at New York University Tisch School of the Arts and has been a guest lecturer at City University of New York College of Technology, Pace University, University of Maryland and University of North Carolina School of the Arts
McCarthy was nominated in 2017 for the Drama Desk Award the Lucille Lortel Award and the Henry Hewes Design Award for Outstanding Projection Design for Notes from the Field at Second Stage and for an IRNE Award in the category Large Theater: Best Projection Design for Notes from the Field at the American Repertory Theater.
McCarthy was nominated for the Henry Hewes Design Award in 2009 for Notable Effects for Frequency Hopping produced by the Hourglass Group at the 3LD Arts & Technology Center in New York City for which she designed both the scenery and projections. The production was noted for its use of a fully robotic orchestra as well as McCarthy's utilization of Musion Eyeliner, which is a modern version of the 19th century Pepper's Ghost effect.
McCarthy was nominated for Best Video Design for Entertainment Today's Ticketholder Award in 2007 for the Center Theatre Group's World Premier production of Lisa Loomer's play Distracted at the Mark Taper Forum for which she designed both Sets and Projections
McCarthy is married, has a daughter and lives in Connecticut.