Kapitáni Strand a Vegová jsou spolu s hasiči ze stanice 126 povoláni do akce na okresní veletrh, když Austin zasáhne „derecho“, série rychle se pohybujících silných bouřek, které způsobí hurikán, tornádo, prudké deště, bleskové záplavy a rozsáhlou zkázu. Owenova nově objevená vášeň pro jízdu na motorce ho přivede na potenciálně nebezpečnou cestu. Tommy má možnost prožít milostný románek, když se seznámí s atraktivním svobodným otcem (hraje ho hostující hvězda D.B. Woodside). T.K. a Carlos se připravují na svatbu, ale hrozí, že jim v cestě za štěstím bude stát tajemství z Carlosovy minulosti.

Kapitán Strand a tým ze stanice 126 se vydají na pomoc ženě uvězněné v pojízdném domku, který unesl její bývalý manžel. Owen se dostane do křížku se svým někdejším úhlavním nepřítelem, seržantem O'Brienem, a pak je vyslýchán FBI. Tommy chce, aby mu Grace poradila ohledně randění. T.K. a Carlos se sejdou s Iris Blakeovou.

As Owen gets pulled deeper into the FBI’s investigation of the motorcycle gang, Sgt. O’Brien makes a confession to him. Meanwhile, Grace and the 126 respond to a call from a man who claims his girlfriend slipped over the side of a cliff and Carlos searches for a missing friend, putting his own life in danger.

As Owen wears an FBI wire for his meeting with O'Brien, The Honor Dogs crash the meet-up and let them know there's an infiltrator in their midst. A frantic TK desperately searches for a missing and held captive Carlos.

Owen helps defend Marjan when a rescue complaint forces her to make a challenging ethical decision. Meanwhile, Grace befriends a young boy who becomes a frequent 9-1-1 caller, but when she discovers he may be in some real danger she must step in.

Capt. Strand reveals to the 126 he has been working with the FBI to help bring down a domestic terrorist group with his Austin motorcycle club/gang The Honor Dogs, then race Owen to respond to a bomb threat at the State Capitol and put a stop to the terrorist deadly plans.

Capt. Strand and the 126 help a husband whose wife "dies" when she is not upside down. Grace takes a call from a pizza delivery driver who is in for the shock of his life. Tommy is worried Trevor's young daughter is a bad seed as she attempts to break them up. Paul is hesitant to go on a date with Asha, who knows him prior to his transition.

The 126 must rescue a father/son involved in a drivers ed lesson gone haywire, then encounter a self-help guru who has lost his self-control. Meanwhile, Owen turns into a "Dadzilla" in helping plan T.K. and Carlos' wedding, and Marjan is suspicious when she meets a couple on her road trip.

On her way back to Austin, Marjan is in for the fight of her life when she is targeted by a killer.

Tommy goes paramedic crew-to-crew against her former employer, private contractors Paragon Medics, as they deal with emergencies involving a dialysis patient and at a perfume factory. Meanwhile, Owen hits it off with a beautiful woman he meets at a fundraiser.

The 126 race to rescue a woman with an arrow shot into her head; Judd is doubly surprised by news Wyatt shares; Mateo helps a family member in need and comes to regret it.

When she discovers her former fiancé is having a baby with his new wife, The 126 help Marjan enter the dating world through a series of chaperoned dates; Owen and the team are called to the rescue when a pregnant woman takes matters (and her anger) out at a motel where she suspects her husband is cheating on her.

Owen is shocked by a secret Kendra has been keeping from him; Grace confronts her father about his past infidelity.

Grace and Carlos work together when they suspect a young woman was a victim of a black market organ trafficking ring; Owen's brother Robert comes to visit and meet T.K., but surprises Owen with news that can affect the Strand family.

When Tommy and Judd disagree on protocol during a rescue at paper mill, a full-on feud develops between the 126 EMS and Fire. Owen awaits news that could change his and T.K.'s lives forever.

Owen is conflicted when his brother Robert asks him for help; Judd and Grace face a family crisis; As T.K. and Carlos prepare for their wedding day tragedy strikes.

Owen is conflicted when his brother Robert asks him for help; Judd and Grace face a family crisis; As T.K. and Carlos prepare for their wedding day tragedy strikes.