Gregg has worked on many hit blockbuster films and projects as leads and featured roles including: X-Men: Days Of Future Past (20th Century Fox), Jupiter's Legacy (Netflix), Jett (HBO) & Granchester (ITV). He has also played lead roles in many West End productions including: Mamma Mia, Shakespeare in Love and Bird Song.

As a Voice Actor, Gregg has extensive experience in Audio Dramas & AAA Video Games, doing not just the voices but Motion Capture as well on award winning productions such as: Assassin's Creed: Valhalla, Syndicate and Origins, Watch Dogs: Legion, Total War: Troy & Horizon Zero Dawn.