A lawsuit filed by one of the Gulf region’s most high-profile expatriate executives could point to a dark side in the mighty Abu Dhabi business empire, if the allegations are proven, and threatens to reignite controversy over several deals, including a major power project in Morocco. The suit has been filed in the United States by former Abu Dhabi National Energy Company (Taqa) chief executive Peter Barker-Homek against his erstwhile employer. Taqa rejects all the charges and has said it will contest the case vigorously.