Del Arco has appeared in a wide range of live theatrical plays. His Broadway theatre debut came in 1987 in Milcha Sanchez-Scott's "Roosters" at the INTAR Theatre. Theater critic Mel Gussow called his a "most sensitive performance", and said his debut was "auspicious". His second Broadway role followed in 1988, when he played Martin in Michael Weller's play "Spoils of War" at the Music Box Theatre, replacing Christopher Collet. This was followed in 1990 by a role in John Jesurun's "Everything That Rises Must Converge" at the Kitchen Theatre Company.