Thomas Philip O'Neill

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Originally from the Back Bay neighborhood of Boston, Tom moved to New York to train at NYU's Tisch School of the Arts where he received his BFA at Stella Adler Studio, the Experimental Theatre Wing, and the International Theatre Workshop: Amsterdam, Holland. He also studied in London, at the British American Drama Academy. O'Neill went on to ... See full bio »

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Known For

Mindhunter Leo Buchanan
FBI Dr. Neil Mosbach / Detective Neil Mosbach
Mapplethorpe David Croland


Hide Hide Show Show Actor (12 credits)
 2021 NCIS: New Orleans (TV Series)
- Stashed (2021) ... Eddie
 2019 Like Mother Like (Short)
 2018-2019 FBI (TV Series)
Dr. Neil Mosbach / Detective Neil Mosbach
- Ties That Bind (2019) ... Detective Neil Mosbach
- Salvation (2019) ... Dr. Neil Mosbach
- Codename: Ferdinand (2019) ... Dr. Neil Mosbach
- Outsider (2019) ... Dr. Neil Mosbach
- Closure (2019) ... Dr. Neil Mosbach
 2018 Mapplethorpe
David Croland
 2018 Freelancing (TV Short)
 2017 Mindhunter (TV Series)
Leo Buchanan
- Episode #1.1 (2017) ... Leo Buchanan
 2017 The Blacklist (TV Series)
- Mr. Kaplan (No. 4) (2017) ... Abe
- The Apothecary (No. 59) (2017) ... Abe
- Natalie Luca (No. 184) (2017) ... Abe
- The Harem (No. 102) (2017) ... Abe
 2015 Black Mass
FBI Wire Tech
 2012 Obey the Giant (Short)
 2011 Boardwalk Empire (TV Series)
- To the Lost (2011) ... Halsey
- Under God's Power She Flourishes (2011) ... Halsey
- Georgia Peaches (2011) ... Halsey
- Two Boats and a Lifeguard (2011) ... Halsey
- Peg of Old (2011) ... Halsey
 2006 Fixed (Short)
Detective Robbins

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Personal Details

Official Sites:

Official Site

Alternate Names:

Tom O'Neil | Tom O'Neill

Did You Know?


Dual citizen of USA and Republic of Ireland. See more »

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