Murtaugh and Cole investigate the murder of an underground MMA fighter when Murtaugh realizes his fighting moves aren't as sharp as they once were. Meanwhile, Trish is unfulfilled by her practice and considers running for a public office. Also, Cole and Erica (guest star Nishi Munshi) try to keep things casual and uncomplicated but their plan backfires when Maya (guest star Shay Rudolph) reacts to her family changes in a negative way.