Intertextuality of "Psycho"

A man transports a lady, who looks paralysed, in the bathroom and places her in the bathtub. He fills the bathtub with water. 

Intertextuality: The bathroom scene is similar and the horrified look on her face

A school girl is walking down the corridors, and heads towards the shower. We can hear someone using the shower, presumably a boy. She silently comes in and comes closer to his cloths. She smells them intensely, which is very weird. She then slowly brings a knife out, looks at it and rubs it against herself. She then approaches the shower, opens the door and strikes the boy showering several times. 

Intertextuality: When he slides slowly down the shower, after she stabbed him and the shot of the boy’s feet at the end reminds us of Psycho.

Towards the end of the film, the stepfather runs after the woman he was living with, to kill her. He follows her to the bathroom, but as she strikes him with a knife on the neck, he falls in the bathtub and holds on the curtains. 

Intertextuality: The fact that he holds on the shower curtains brings us directly to the shower scene in Psycho.