Knock knock stars Keanu Reeves as the family man who falls into temptation and Lorenza Izzo and Ana de Armas as the seductresses who wreak havoc upon his life, turning a married man's dark fantasy into his worst nightmare. Architect and happily married husband Evan Webber has the house to himself on Father's Day weekend while his wife and children go on a family-planned beach trip. His wife Karen, a successful artist, leaves their assistant Louis in charge of her sculpture that needs to be moved to an art gallery. Alone in his beautiful and expensive home, Evan works on renderings for an ongoing house project. Two nubile, stranded women reveal a sinister agenda after they spend the night with a married architect..