[1][2] O'Connor big break was in 2014 as Olly in the HBO fantasy television series Game of Thrones.

"[6] O'Connor has also appeared in several other roles, including Peter Cratchit in the BBC One series Dickensian, which premiered in December 2015.

[2] He's appeared in a music video with Noah and the Whale as well as several television commercials for Haribo, and as a lead character part in one episode of Holby City.

[2] On stage O'Connor has performed in front of audiences on the tour of Cameron Mackintosh's Oliver!, playing the part of The Artful Dodger alongside Iain Fletcher, Neil Morrissey and Samantha Barks.

It was scheduled to premiere on Broadway at the Lyceum Theatre in Spring 2020 with an Original Cast Recording already released.