[1] He then took on the roles of the Dauphin and of Lord Scroop in a Shakespeare's Globe production of Henry V, where his performances received praise.

[11] In late 2012 until 2013, Egyiawan performed in an all-male double feature at Shakespeare's Globe, where he was cast as Richmond and the Duchess of York in Richard III, as well as in the roles of Valentine and an officer in Twelfth Night.

[12] Egyiawan then took on various supporting roles in an English production of Aimé Césaire's political play A Season In the Congo.

[13][14] From November 2013 to February 2014, the double feature of Richard III and Twelfth Night moved to the Belasco Theatre on Broadway, where Egyiawan received praise from American reviewers and press for his performances.

[27]From 2016 to 2017, Egyiawan was part of the main cast of the Fox network's American supernatural horror series The Exorcist, playing Father Devon Bennet.

[30][31][32] In 2018, Egyiawan joined the cast of Mood Music at the Old Vic Theatre, playing the role of Miles.

[38] The same year, Egyiawan was cast in the guest role of Roger Barrowby in the British spy thriller Slow Horses.

[39] Egyiawan was also a recurring cast member in season 1 of HBO's House of the Dragon, playing Grand Maester Orwyle.

[39] In 2024, he played the recurring role of Adrian in the British mythological dark comedy Kaos, before it was cancelled after one season.