(written from a Production point of view)
Addai is probably best known for her role of Naevia, a part she took over of from Lesley-Ann Brandt for the second and third season of the drama series Spartacus: Blood and Sand (2012-2013, working with Peter Mensah and Nick E. Tarabay) and for her recurring role as A.R.G.U.S. Agent Amanda Waller on the second and third season of the comic adaptation Arrow (2013-2015).
Born in London, England, UK she moved to the United States in 1989 where she was raised in a suburb of Washington, DC. She attended the Montgomery Blair High School in Silver Spring, Maryland and the Tisch School of the Arts in New York City. 
Addai-Robinson started her career with guest roles in episodes of The Education of Max Bickford (2002), Law & Order: Trial by Jury (2005, with Bebe Neuwirth), Law & Order: Criminal Intent (2005), Justice (2006, with Victor Garber), CSI: Miami (2007), Dirt (2007, with Jeffrey Nordling), Entourage (2007, with Mike Hagerty), and Life (2007, with Roger Aaron Brown and Leigh Taylor-Young). She also appeared in the television science fiction movie A.M.P.E.D. (2007), the television comedy Dash 4 Cash (2007), and the drama Mississippi Damned (2009, with Benjamin Brown).
Between 2009 and 2010 she portrayed the recurring role of the nurse Debbie in six episodes of Brannon Braga's science fiction series FlashForward along with John Cho and Gabrielle Union. She appeared in the television drama Edgar Floats (2010, with Derek Webster and Miguel Ferrer and art direction by Ramsey Avery), the crime drama Colombiana (2011, starring Zoe Saldana), and the television drama Jodi Arias: Dirty Little Secret (2014, with Jen Oda and Tony Plana). Further television roles includes episodes of Numb3rs (2009, with Ray Wise), CSI: NY (2009, with Robert Joy and Geoff Meed), NCIS: Los Angeles (2012, with Daniel Dae Kim), The Vampire Diaries (2013, with Rick Worthy), King & Maxwell (2013), CSI: Crime Scene Investigation (2013, with Wallace Langham), Dallas (2014, with Brenda Strong), and Ambiance Man (2014).
She reprised her role as Amanda Waller in 2014 when she lent her voice to the video game Lego Batman 3: Beyond Gotham. Other voice artists in this game include Olivia d'Abo, Nolan North, Clancy Brown, Robin Atkin Downes, Fred Tatasciore, Bumper Robinson, and Marc Worden.
More recently, Addai-Robinson appeared as Emily West in the television mini series Texas Rising (2015, with Jeffrey Dean Morgan, Christopher McDonald, Robert Knepper, and Geoffrey Blake) and wrapped filming for the drama The Accountant (2016, with Fernando Chien and Dennis Keiffer and production design by Keith P. Cunningham).