Koko and his friends are spending summer vacation on the shores of a lake near the idyllic Green Hill, hanging out and playing. The magical countryside is disturbed by unusual events which alarm the children as well as the locals: under cover of night, burglars break into one house after another. When the police turns a blind eye to denunciations by adults, the children decide to take matters into their own hands and unmask the burglars.
| Writing | Ivan Kušan | Novel |
| Directing | Čejen Černić | Director |
| Sound | Dinko Appelt | Original Music Composer |
| Writing | Hana Jušić | Writer |
| Production | Ankica Jurić Tilić | Producer |
| Production | Hrvoje Pervan | Producer |
| Camera | Danko Vučinović | Director of Photography |
| Editing | Slaven Zečević | Editor |
