TK gets a huge surprise on his 30th birthday when his stepdad Enzo arrives in Austin along with TK's young half-brother Jonah; Owen's resentment of Enzo turns physical; Tommy is determined to push through her latest crisis; Wyatt attempts to talk-down a suicidal caller and the 126 must perform a dangerous surgery in the field after a man is impaled in a tree.

A gang killing leads Carlos to new information on his father's murder. TK contemplates a major life decision as Owen is determined to get Austin's first responders' health care coverages increased.