3 Body Problem' Director Derek Tsang Joins DEA Series 'Group 41 Derek Tsang boards ‘Group 41,’ a DEA true-crime series from Jonah Greenberg, producer of Zhang Yimou’s ‘Shadow,’ at TCCF in Taipei. Derek Tsang boards ‘Group 41,’ a DEA true-crime series from Jonah Greenberg, producer of Zhang Yimou’s ‘Shadow,’ at TCCF in Taipei.