A woman named Erin has traveled with her boyfriend, Crispian Davison, to a vacation home in rural Missouri. It is a family reunion held by Crispian’s parents, Aubrey and Paul. Also joining them is Drake, Kelly, Felix, Aimee, Zee, and Tariq. Drake is Crispian’s older brother and Kelly is the former’s wife. Felix and Aimee are Crispian’s younger siblings – their partners are Zee and Tariq respectively. Unbeknownst to this family, a man wearing a lamb mask has recently killed a woman, writing the words “You’re Next” in blood. This simple reunion will hit a snag when this killer decides to pay a visit.