Biography
Thomas Philip O'Neill is an American actor. Originally from Boston, he trained at New York University’s Tisch School of the Arts, receiving a BFA through the Stella Adler Studio, the Experimental Theatre Wing and the International Theatre Workshop in Amsterdam. He also studied at the British American Drama Academy in London and later apprenticed at Stella Adler Studios under master teacher Alice Saltzman.
O’Neill is known for his role as Leo Buchanan in the Netflix series Mindhunter (2017). He has appeared as Dr Neil Mosbach in the CBS series FBI (2018–), as well as in Black Mass (2015), Mapplethorpe (2018) and guest roles in The Blacklist, Law & Order: Special Victims Unit and NCIS: New Orleans. He is the grandson of former Speaker of the House Tip O’Neill.
