What is an insidious plot?

Answer 1

Insidious is About a Boy who goes into a coma and his parents sees demons enter their house. So they call a psychiatrist to help them and she brings two ghost catchers. They then find out that it's not the house thats haunted, it's their son. As the fathers mom is invited, she tells them that the father once went through the same thing. So he is told to fall asleep and retrieve his son in a place called the further. He falls asleep then gets past through obstacles such as a smiling family or a demon fighting him. Later, he retrieves the boy and gets out of there. In the end, the boy is saved but the physiatrist dies because the boys husband strangles her. She then looks in the camera and notices that the dad is still in the further and his body is replaced by a demon.