How utterly ridiculous The ending beggars belief. Boyd orders the team to walk away from three people who he knows are involved with organ trafficking. He also knows that two of the men are going to kill the other one.
The longer the series went on the more outrageous Boyds conduct becomes. He verbally abuses his team, breaks laws to get evidence, and verbally and physically abuses prisoners. He has apparently convinced himself that the end justifies the means.
The overall plot is interesting but the excesses of the Boyd character spoils the show. In real life Boyd would have been dismissed from the force or all his team would have resigned.