Jimmy Blue, lead detective, Yolanda Rodriguez and the team's computer specialist, Tessa are brought in to solve a gruesome case of decapitation. With no time to waste and the body count rising, they dive into the clues in a desperate search for the killer.
A nun has been murdered, a community shattered and everyone's faith in humanity is put to the test. Secrets , inner demons and dark memories begin to crack the surface of the smooth running SIU.
A new detective, Tarik, joins the team after lending a hand on their last case. The Mayor's son is missing and SIU is brought in to solve the case quietly and quickly. Clues lead to an underground gambling ring and an elite criminal organization, The Dragon's Shadow.
When a former Russian diplomat ends up dead ,the SIU team is called in for a particular reason. Suddenly, the team finds themselves being pawns in an international conspiracy involving Russian money laundering, CIA spooks and former KGB hitmen.
A new designer drug is killing kids. Jimmy and his team dig and in turn the city upside down looking for the dealer. Dead bodies start to mount, and personal lives are torn apart as the head of the Albanian Mob, Argon, finally discovers who took his money. More importantly, Argon finds out who killed his son.
Everything comes to a head as Argon closes in on Jimmy and Darius. Jimmy is starting to crack as the world closes in around him. He can see the writing on the wall ... the end is coming.
Something terrible and unimaginable has happened. Jimmy Blue has been shot and the team is reeling from shock. Tarik, Yolanda and Tessa thrown themselves into solving the case, but hit dead end after dead end. Miriam shows up at the hospital saying she knows who shot Jimmy. But, the deal she is offering may hurt Jimmy more than help.
Yolanda and SIU throw themselves into solving Jimmy's case. Miriam works along side SIU. Respect growing between them. They retrace their steps. They follow old leads. When left with the facts they can come with only one conclusion ... SIU has a dirty cop. Now the four of them are isolated and have to work outside the system.
The team is still reeling from Jimmy being shot. But, now they have a witness they are hiding from everyone as the SIU team secretly work to solve Jimmy Blue's attempted assassination. The Team is also flourishing under Yolanda's capable leadership and now SIU has been given a special commission to work all five boroughs in NYC. Their first case is a mystery wrapped in a riddle as they hunt down a serial killer and sexual predator preying on innocent women. But, they have an even bigger threat looming in the shadows.
Chief Wryles breaks his silence and give us a glimpse into his master plan. But, his world goes sideways when Darius resurfaces and blackmails him. SIU has its hands full with a bizarre murder triangle of a high-end fashion model. Gloria admits a painful secret she's been hiding from Jimmy and Jasmine is battling her own demons as she confronts her feeling about Yolanda.
Tarik and Tessa are becoming leaders in their own right. The crime world is stirring, and SIU finds themselves in the middle of a war. Then, as luck would have it, they get a key piece of information linking Jimmy's shooting to Argon. Tarik and Han go head to head in a battle of wits to find Jimmy's killer and once the dust settles, no one will be the same.
The sins of SIU have come back to haunt them. A team member has been kidnapped by a highly intelligent vigilante. The Vigilante's motives become clear and has been plotting for a long time. As the Vigilante's master plan draws to its conclusion the question becomes will SIU join him in his crusade or will they stop him?
Jimmy is up and about and staying away from SIU. Miriam and Zakia continue to work the case against Argon, but Argon and Han are plotting, and their plans are unfolding. Darius and Argon continue their 'business' partnership with Darius' daughter held as a bargaining chip. The team is falling apart, but through it all they are still SIU.
The team's personal and professional life come crashing together. Argon manipulates SIU to his own ends, while Han plots a bigger goal. Tess and Tarik try to hold down SIU as Yolanda becomes more erratic. She reaches out to Jimmy, only for him to shut her out. Jimmy and Darius finally meet, but it can only end at gun point. No one escapes the disastrous fallout of this episode's season finale.
