Johan Theorin, and yet still very good

Having read the first installment of 3 Johan Theorin, I expected to find myself again on the island of Öland in Sweden but not this time around, everything happens on the continent.
A nursery school was built in the grounds of a psychiatric hospital are locked up more or less dangerous mental patients, since it gives psychopath killer. The school and the hospital are connected underground to enable children to visit their parents in a confined education precursor mode.
January Hauger young puériculteur we follow throughout the book, gets a job in kindergarten because of course he has an interest to get in touch with a person who is confined in the hospital. With all the risks involved and all contact sockets more or less dubious taken in the hospital and even to his colleagues of motherhood.
As for "The Hour Trouble", several feed back 2 periods in the past of our hero (hero is a big word for fool would be the most appropriate term) to explain his situation, his disease linked to a live event of his adolescence that allowed him still to meet the person he wants to see and suppose confined in the hospital.
What I like about Johan Theorin is that it is useless to try to guess as we evolve from one surprise to the outcome that is totally unexpected and really involved in the final pages. And is fun to read because it is held in suspense knowing that we will be surprised by the twists.
The many chapters make easy reading, the more one is not too much in the description, the writing is very nervous.
Question atmosphere, I admit I preferred the previous novels.
Nevertheless, Johan Theorin is an author that I am because I was really excited Hour Trouble and L'Echo des Morts.