Chief:

Times have been good to Turk Dennison, and his old lady, Trinity. But as the days go by, their love for what they do has dwindled. They're both feeling burned out and ready to start the next chapter of their lives. Retirement. And oh, how he looks forward to future lazy mornings and spending the days hanging out with his brothers and loving on his wife.

Trinity:

With each new case that's crossed Trinity's desk, a forlorn feeling has wrapped itself around her. Her heart has been broken one too many times by the system. It's time to call it a good, productive life, and know that in her heart, she's done the very best she can for all of the kids that've come through her life. Now, it's time to pass the reins to her youngest daughter, Cora.

With Christmas right around the corner, they celebrate with their friends and family while getting ready for all of the festivities that accompany the holiday. While doing so, tragedy strikes another family. She and Chief decide to step in and mentor the remaining parent, as well as help him and his children while they heal.