Wick and Michael welcome back their partner, Kathleen Ryan, after a stress-related leave of absence. They save men from a building that exploded. Kathleen makes a hero save of a man in a downed airplane that falls down a mountain. A woman that the team has visited before dies from being shot by her boyfriend.
The 27 and the 77 are playing pranks on each other. A Russian woman's grandfather is having chest pains. The squad rescues a teenager who falls while trying to hang a banner at his high school. Wick, Michael and Kathleen are caught in sniper fire while later answering a false alarm at the same high school. The shooter shows up at the firehouse. Kathleen deals with her ex-boyfriend.
College celebrators keep everyone busy, and steal 77's R.A. Wick performs a risky surgical procedure in the field, but the doctor that is going to write him up instead learns what it means to improvise. Michael's father tries to convince him to take over the family business. Kathleen is preparing for an amateur crossbow tournament in New Zealand.
A man is busy destroying the house he shares with his gay lover when his electric saw kicks back on him. A man destroys his ventriloquist's dummy in a fit of jealousy. Megan and Michael are running into some stumbling blocks in their relationship. An accident traps a couple on their wedding night, and it's clear that the groom is not going to make it out alive.
A new firefighter joins the team and is mercilessly pranked. Bell is upset when he loses a little girl whom he thought had a chance. The team rescues a man from a rushing river. Wick investigates a serial arsonist. Bell finds out his ex-girlfriend is marrying his brother.
Ryan almost ends up getting herself killed when she refuses to abandon a boy trapped in a shaft filling with water. Bell's father has a heart attack and Bell tries to hold the company together despite his younger brother. Megan is upset that Bell can't confide his feelings in her, and turns to an exboyfriend for comfort. Wick saves an actress from a rubber suit and gets bit by the acting bug.
Ryan and Wick are trapped after a chemical explosion. Even after they are rescued, they have trouble dealing with the possibility of future birth defects in their unborn children and the fact that Bell let the door close on them, trapping them inside the dangerous building.