This movie is based on the Swedish children's book series called "LasseMajas detective agency" by Martin Widmark. The book series, now running well over ten books, is immensely popular in Sweden and is about two friends, a boy (Lasse) and a girl (Maja), around ten-eleven who are running a detective agency in a quaint make-believe Swedish village called Valleby, where nothing every happens - at least nothing violent. Thus, the friendly police officer in town is completely untrained in his profession, why he often welcomes the assistance of the young detective couple. I am not going to write too much about the plot (why spoil it?), more then to say that someone is out to discredit the police officer...
The manuscript, however, is not based on any of the books and is not written by Martin Widmark. But Sara Heldts original manuscript nicely follows the feeling of the original books. A special note about the cinematography, which nicely captures Helena Willis original illustrations in the book series. The photography is also an important part of why it becomes such a successful adaptation.
I went to see it with my wife and my two sons and we all enjoyed it to varying extent. Of course, my eldest son thought all the "love-stuff", especially the romantic awakening of Lasse, was awfully embarrassing and a waste of time (he is in that age). It is fun, exciting (but not too exciting), romantic (in a very silly way), scary (but not too scary) and simply adorable. My wife is too "grown-up" to admit she liked it, but me and my youngest son both loved it. The acting may not have been too convincing, but there is a surrealistic/fairy tale feeling to the whole movie that excuses a lot of weird behavior and lack of consistency that grown ups tend to get annoyed with.
To sum up, a seven, maybe much for a very predictable little story with implausible characters, but then I am childish and would not mind living in Valleby...