British-Nigerian Okoh, who scoops the £16,000 prize fund - the competition's largest single award to date - impressed the judging panel made up of writers Simon Stephens (chair) and Jackie Kay; actors Sue Johnston and Maxine Peake; Royal Exchange joint artistic director Sarah Frankcom and chairman of Bruntwood Michael Oglesby.
Okoh's previous works include Egusi Soup, which premiered at the 2009 Hotbed Festival and was toured by Menagerie. Okoh was also a runner-up for the 2011 Verity Bargate Award 2011 for The Real House.
The panel also awarded three Judges’ Awards to Alistair McDowall for Brilliant Adventures, Gareth Farr for Britannia Waves the Rules and Louise Monaghan for her play Shadow Play. Each of the Judges' Awards winners walks away with £8,000.
As previously reported, the Bruntwood Prize, the UK's largest playwriting competition, this year received 2,188 entries. Of those who submitted scripts, 52% had never written a play before, with 76% being new to the competition.
All four award winners will now have the chance to develop their play with the Royal Exchange, with a view to production. In addition, leading theatre publishers Nick Hern Books will publish all winning plays that receive a production at the Exchange.