Chicago-based Critical Mass has lost its executive creative director to crosstown agency Manifest after approximately six months.
Sacha Reeb, who joined the Omnicom network in London nearly three years ago, is now chief creative officer at Manifest, an independent agency.
After being hired to help oversee the work of Critical Mass in the U.K. in 2014 and sitting on its executive creative council, Reeb moved from his home base to Chicago early this year.
The reasons for that transition and his subsequent departure are not clear at the moment.
Prior to joining Critical Mass, Reeb held top creative roles at such digital, design-focused agencies as Huge, Organic and Razorfish. He was also chief creative officer at Grey Germany.