McInnis debuted as an actor in the 1999 American indie crime thriller The Cut Runs Deep, which was an underground hit in South Korea, where McInnis moved to soon after quitting school and achieved noticeable success in the Asian film industry. He was the face of SK Telecom's UTO division from 2001 to 2003 while in Korea, and his early Asian film credits include a supporting cast role in A Moment to Remember.

After a period of introspection, McInnis returned to the limelight with a leading role in Typhoon, a big-budget South Korean action film released in 2005. McInnis went on to star in critically acclaimed American-Korean romance film Never Forever, then took on a supporting role in Epitaph, and guest starred in MBC's television series Air City.

He set up a spice Business, McInnis MasterBlend, in 2006 with his father.

In March 2018, McInnis signed with new management agency Saram Entertainment.