Detective Comics Annual #2

It's a terrible, dangerous time to be a cop in Gotham City. At a time when police are being targeted for assassination, Gotham's Finest also face a threat from within, as a shape-changing identity thief has infiltrated the GCPD and threatens to destroy it from within. Will he unravel the mystery behind this secretive killer before he loses any more of the few allies he has left on the force?