9-1-1: Lone Star

The 126 race into action when an armored truck and its guards are attacked by a group of masked men; Owen attends group therapy with Tommy to deal with his brother Robert's death; Marjan and Paul each apply for the open lieutenant position.

The 126 race into action when a major train derailment causes multiple injuries; Tommy makes a bold move in her relationship with Trevor; Wyatt asks Owen to give Judd his job back.

The 126 race to contain a toxic chlorine cloud of death unleashed by the train derailment; Owen names the station's new lieutenant.

The 126 are called on the scene to a hoarder's rat-infested house, then are trapped in an elevator as a woman goes into labor; Tommy and Trevor host his ex-wife Cassandra for dinner which goes awry.

The 126 race into action when a horse barrels into a brewery with an unconscious rider on its back and then to a bus full of tourists all experiencing seizures. Judd introduces Owen to Wyatt’s mother Marlene. Carlos and T.K. start couples counseling, when Carlos investigation into his father’s murder becomes all-consuming.

The 126 race to save a man crushed under a vending machine; Owen finally faces the truth of his brother's death; Tommy is concerned that Nancy may be facing a possible health scare.

TK gets a surprise on his 30th birthday when his stepdad arrives in Austin; Owen's resentment of Enzo turns physical; Wyatt tries to talk down a suicidal caller; 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; Owen is determined to get Austin's first responders' health care coverages increased.

Carlos is determined to solve his father's murder; Owen is offered a life-changing opportunity; Judd gives into his demons; Tommy begins her treatment.

Judd literally walks straight into the line of fire when an armory catches on fire, sending bullets flying everywhere; Owen questions Judd's pledge of sobriety; Marjan introduces her boyfriend Joe to her visiting parents.

Owen makes a decision about his future; Tommy receives devastating news; T.K. and Carlos worry about adopting Jonah; Mateo gets his immigration status threatened after an altercation; a doomsday prepper gets trapped in a bomb shelter and The 126 and all of Austin brace for an asteroid crash.

Owen and the 126 deal with the aftermath of the asteroid crash in Austin while an even greater threat looms.