Contains spoilers for this episode.
Matt patrols Hell's Kitchen through a heatwave, stopping armed robbers while Nelson and Murdock struggle to pay their bills. Their reputation brings clients through the door, but food offered in thanks cannot cover the rent. Foggy worries about Matt's injuries and the possibility that a night on the streets will kill him. Their evening at Josie's changes when Grotto, a survivor of a massacre at an Irish gang gathering, asks the firm for help obtaining witness protection.
Grotto collapses from a wound he has concealed, and Karen accompanies him to the hospital. Matt and Foggy visit the crime scene and learn that other criminal groups have also been attacked. The scale and precision of the violence initially suggest a new organisation or a trained squad. Foggy questions a biker contact while Matt follows a weapons lead into another scene of slaughter, finding men suspended in a meat locker.
One dying victim tells Matt that a single man is responsible. That gunman reaches the hospital and attacks Grotto, forcing Karen to flee with him through the building. Matt intervenes before the pursuit can end in another killing and fights the attacker on nearby rooftops. The stranger proves able to withstand and return his blows. When Matt gains ground, the man draws a smaller gun, says one word and shoots him off the roof.