Quoc: Thomas Patrick Cavanagh (born October 26, 1963) is a Canadian actor and director best known for a variety of roles on American television, including starring roles in Ed (2000 -- 2004), Love Monkey (2006) and Trust Me (2009), and recurring roles on Providence and Scrubs. Since 2014, Cavanagh has served as a series regular on The Flash, portraying various versions of Harrison Wells.

Answer this question based on the passage: who plays dr harrison wells in the flash?
HW Chung: OK, some thoughts:
The important part for answering this question is: Since 2014, Cavanagh has served as a series regular on The Flash, portraying various versions of Harrison Wells. The answer is Thomas Patrick Cavanagh.