Armed Reaction IV (Chinese: 陀槍師姐 IV; Jyutping: to4 coeng1 si1 ze2 IV) is a Hong Kong modern cop drama released overseas in August 2003. The drama stars Bobby Au-yeung and Ada Choi as the main leads with Joyce Tang, Marco Ngai, Mimi Chu, Frankie Lam and Yoyo Mung in main supporting roles. Original broadcast of the series began on TVB Jade channel from February 2 till April 9, 2004 at 9:30-10:30 p.m. timeslot with 40 episodes total.