The witness who testified against D'Angelo is killed and the Barksdale organization is suspected. In light of Phelan's pressure, a detail is formed to investigate their activity in the towers and the pit. However, the detail's lieutenant, Cedric Daniels, is concerned with the quality of the team assigned by Deputy Ops. Ervin Burrell, while McNulty is concerned with the department's plan for the investigation, believing the approach of "buy busts" won't get them anywhere near the high-ranking members of the organization. The operation begins with Daniels' protégé Kima Greggs using Bubbles to identify who's who on the street. Meanwhile, McNulty and his partner, Bunk, try an unusual interrogation approach with D'Angelo, while Burrell tries to keep the death of the witness out of the press. Later, Daniels' suspicions about his team prove correct when an unauthorized late night foray into the towers by Herc, Carver and Prez goes awry.