Complex sentence: Bellwether shoots a serum pellet at Nick to make him kill Judy, and frames a call to the ZPD, but Nick had disarmed Bellwether's dart gun by replacing the serum pellets with blueberries.
Split into simpler sentences: Bellwether shoots a serum pellet at Nick to make him kill Judy, and frames a call to the ZPD. Just before Judy is killed, it is revealed that they had disarmed Bellwether's dart gun by replacing the serum pellets with blueberries.