Born in Okinawa Japan, Seamus Mulcahy grew up in a Military Family. He is the oldest of four boys.  After graduating from Kubasaki High School,  in Japan, he attended various acting programs including The London Dramatic Academy  and the Chautauqua Institute.

He then moved to New York City, where he worked at various shows before landing a friendship with the Shakespeare Theater of New Jersey, under the direction of Bonnie Monte. During this time he appeared in countless productions earning his membership in Actors Equity.

When off stage, Seamus founded and directed The Dog Film Company and their first film Shakespaws, a DVD for dogs and dog lovers. Shakespaws is a collection of famous Shakespeare scenes performed by  dozens of different types of dogs. Shortly after Shakespaws, Seamus worked on two production: King Lear, as the Fool, at the Shakespeare Theater of New Jersey with Daniel Davis and Master Harold and the Boys, at Delaware Theatre Company. These two experiences, though highly successful, turned Seamus to the idea of Graduate School.  In the winter of 2009 Seamus was casted in hit Off Broadway revival of Our Town, directed by David Cromer at the Barrow Street Theater. The show ran for over three years, however Seamus left after six months to appear in his first leaning role as Tab in ONE FALL, directed by Marcus Dean Fuller.


The week after the film wrapped Seamus started his first year at the Yale School of Drama’s acting program. While at Yale, he and a group of theater makers created a team called: Over Head Projector. They would collectively devise such productions as: Salome, Tall Tall Skinny Boys, Dr. Faustus Lights the Lights, The Henry Dodger Project and A Christmas Carol.  He is also a member of The Wilsons, The acting class of 2013, which includes the talents of: Will Cobbs, Hallie Cooper-Novack, William DeMeritt, Lucas Dixon,  Laura Gragtmans, Chris Henry,  Miriam Hyman, Fisher Neal, Lupita Nyong’o, Michael Place,  Jillian Taylor, Adina Verson and Brian Wiles.

Seamus’s Yale School of Drama credits include: Konstantin Treplev (The Seagull, directed by Alexandru Mihail) Octavius Caesar (Antony & Cleopatra, directed by Margot Bordelon)  Bob (A Thought in Three Parts, directed by Hallie Cooper-Novack) Five Production with Over Head Projector under the direction of Lileana Blain-Cruz. Nicholas Stoughton (Elijah by Michael Mitnick directed by Christopher Mirto). And Henry VI,  Henry VI War of the Roses, directed by The Wilsons.  Seamus was also in The Yale Rep production of Romeo and Juliet, as Peter, directed by Shana Cooper.

Since graduating from the Yale School of Drama, Seamus was casted in his first TV movie, Killing Lincoln with Tom Hanks, which aired on the National Geographic Channel. He played David Harold, one of the three conspirators who aided John Wilkes Booth. His first play out of school was Billy Witch, at APAC in Queens, written by Greg Moss and directed by Erik Pearson. He has recently recorded a web-pilot with Sheri Rene Scott, has returned to The Shakespeare Theatre of New Jersey, as George Dupont in Tovarich, and has been a cast member in the on going workshop of Teeth and Feathers written by Charise Castoro Smith (New Dramatist and Atlantic Theater).

Seamus went to LA to do a production of Rabbit Hole, playing Jason, at the La Mirada Theater in Los Angeles, directed by Michael Mathews. Followed by a new play at the Pasadena Playhouse, ABOVE THE FOLD, starring Taraji P. Henson, written by Berine Weinraub, and directed by Steve Robman. He returned to The Shakespeare Theater of New Jersey for a ground breaking adaption of Ben Johnson’s THE ALCHEMIST directed and written by Bonnie Monte.

An Epic theatrical event occurred when he played Prior Walter in ANGELS IN AMERICA: The Millennium Approaches & Paristrika at The Kansas City Rep, directed by Tony award winner David Cromer.  Later that year he co-stared in his prime-time debut on CBS’s Elementary as Ernie Jacobs in “Burden of Blood.”

The next year Seamus found him self very busy with many projects.  He got perform in South Carolina, where his parents currently live and reprise a role he played at Kubasaki High School, Okinawa Japan on  Hilton Head Island, performing in THE MOUSETRAP at the Coastal Carolina Art Center.   The show closed on a Sunday night and on Monday morning he flew to Los Angels to start rehearsals for Jesse Eisenberg’s West Coast Premier of THE REVISIONIST opposite Tony award winner Denna Dunagan at The Wallis Annenberg Center in Beverly Hills.


Casting Director Jack Doulin invited Seamus to join New York Theater Workshop’s Dartmouth Residency to workshop The Oslo’s Winter Guests Theatre Company’s “America Ep. 2 Pyschopatriot.”  That winter he would go on to do Dylan Thomas’s A CHILD’S CHRISTMAS IN WALES at the Shakespeare Theater of New Jersey, directed by Joesph Discher.

Baltimore Center Stage brought Seamus to workshop and perform in The Young Playwrights Festival directed by Michael Wiggins.  He was lucky to return to Baltimore Center Stage the following year to do The Young Playwrights Festival again, this time as a hamster singing David Bowie’s Space Oddity.


Returning to his ‘theater home’ at The Shakespeare Theater of New Jersey, Seamus played the famous John Webster in SHAKESPEARE IN LOVE along with his best friend Dublin, his nine year old Boston Terrier who played Spot.  Seamus got Dublin to perform the role which stole the show. To this day patrons of the theater ask “When is Dublin coming back?”

Recently Seamus Mulcahy Stared in CHARLEY”S AUNT in the title role of, well… Charley’s Aunt. But really, Lord Fancourt Babberly at The Shakespeare Theater of New Jersey, Directed by Joseph Discher. While running the show, he was also in rehearsals for THE WINTER’S TALE where he played The Clown, again at STNJ, directed by Bonnie Monte.

The New Year brought with it a new play. The second workshop and reading Seamus has done for VILNA, a true story about a city in Poland during the Holocaust, written by Ira Fuchs and directed by Joseph Discher. The had its official opening February 20th 2019,  Off Broadway at the oldest Off Broadway theater, The Theater at St Clement’s. Starring Mark Jacobi,  Sean Hudock and  yours truly.

Seamus is currently in The Ensemble Studio Theater’s 37th Marathon of One-Act Plays: JESUS IN MANHATTAN by Kate Atwell.  on 52nd St between 10th and 11th ave, June 9-29 2019.