Ellis Whitmore is arrested on a Tuesday morning. The case closes. But for Nate Brannick, what comes after the truth is harder than what came before it.

This is the final episode of Next of Kin.

A name surfaces. A county file is unsealed. The DNA tells a story about a family that rewrote its own history, and Grimes begins to understand what Tom Brannick found — and what it cost him.

Claire Brannick kept files. Thirty-one years of child welfare cases, and buried in the paperwork, a trail that leads somewhere no one expected. Grimes follows it. She doesn't like where it goes.

The DNA results come back. The case against Nate Brannick starts to crack. Grimes drives two hours to a dead man's house and finds the questions she should have been asking from the beginning.

Nathan Brannick is missing. His father is dead. The evidence points one direction, and Grimes follows it — into an arrest and a crime scene that tells a different story than the one everyone wants to hear.

A housekeeper named Maria Gutierrez is seventeen minutes from the end of her shift. A retired man is dead in a bathtub two doors down. And Detective Grimes is about to walk into a case that will unravel everything she thinks she knows about a family.

Three weeks of dead ends. Three weeks of cologne and alibis and false trails that all led somewhere loud... and nowhere true.

Then Mark Frost walks into the precinct. Unshaven. Sleepless. Carrying a laptop full of secrets and a story that changes everything.

There was a project. A press release set to send. A senator about to cross the most dangerous line in politics. And someone who decided that the cost of that crossing... was his life.

The truth has been hiding behind the one person Grimes stopped looking at. And the evidence was purchased six months before anyone knew there would be a murder.

She wasn't on the guest list. She came in through a service entrance, in a dark coat, with tears on her face. She wanted one thing: for the Senator to hear her son's name.

Three months earlier, a twenty-three-year-old college student walked into a convenience store to buy milk... and never walked out. The gun that killed him was manufactured by the Senator's wife's family.

Now Grimes has a new face on the board. A grieving mother with a motive shaped like a bullet. But grief and guilt don't always point where you think they do... and the deeper Grimes digs, the more she realizes this case isn't about who was angry enough to kill. It's about who was afraid.