On stage, Ajala has performed in
Nation, ''
A Midsummer Night's Dream with the Royal Shakespeare Company, Hamlet, and as Jim Brown in the European premiere of One Night in Miami'' by
Kemp Powers. In film, his first part was in
Kidulthood, and he also appears in the sequels,
Adulthood he has also appeared in
The Dark Knight Sean 'Mac' McAlister, a character from 2017 video game
Need for Speed Payback, is voiced by and modeled after him. Ajala has appeared as Keith in the BBC Radio 4 dramas
Burned To Nothing (2011) and Felix in ''The Price of Oil: Someone's Making A Killing In Nigeria'' both by Rex Obano. In 2018 and 2019, Ajala played
Manchester Black in seven episodes of the fourth season of
the CW series
Supergirl. From 2020 to 2024, Ajala had a main role as Cleveland "Book" Booker in the third through fifth seasons of
Star Trek: Discovery. The series was released on
CBS All Access and then on
Paramount+. In September 2025, it was announced Ajala had joined the cast of the long-running
NBC series
Law & Order for its 25th season. ==Personal life==