One of the two best episodes of season 4 (see Deliver Us From Evil) this is a riveting episode no matter how you slice it.
On a domestic call, Sonny inadvertently shoots a teenage boy. The usual outcry from people less interested in justice than promoting themselves ensues. More important, Sonny is torn up about it.
He tries to reconnect with his own son, Billy, as ex Caroline drops her engaugement news on Sonny and tries to convince him to give up parental rights.
The problem with the case is that no one is who them seem to be. While more well known now, Ving Rames and Danitra Vance are wonderful as the "parents" and Issac Hayes shines in a small role.
Even after a final revelation about the boy's identity comes out, Crockett doesn't change his stance. He also makes a decision about Billy too.
The emtional tug of war between Crockett and Castillo is a highlight of the series.