21 year-old Isi leads a normal, middle-class life. She has everything she needs to lead a normal life, or at least she seems to be satisfied with what she has. But she is mentally fragile and unstable, a condition which she is able to cover up skilfully with her sarcasm. However, her parents' broken marriage and daily fights; the sudden and unexpected separation from Ben, her boyfriend; her subsequent failure at Art School; and, finally, the stubbornness and cold-heartedness of her "best" friend, all lead to a severe psychotic crisis with suicidal impulses. When her suicide attempt fails, she starts to review her attitude towards life. More or less of her own free will, she volunteers to an alternative psychiatric treatment study called "P.U.L.S.E." (Prosocial Uniting Life Stabilization Experiment) which is headed by Prof Dr Harry van Maast. On the way there she meets Eddy, who is also participating in the P.U.L.S.E. programme. Eddy and Isi enter the P.U.L.S.E. treatment complex and soon discover that they are not the only ones who form part in the programme. This is the beginning of exciting and dramatic highs and lows between the characters, their past, present and future – a story full of unexpected turns while it remains exciting and yet emotional. The development of the participants of the programme stands in the foreground. Dr Harry van Maast believes in his new, but at times also very unconventional treatment methods. But who directs him? Who is the mysterious caller that seems to be giving him orders and instructions over the telephone? Could it be that the decisions are not even his own?