If You Go Down in the Woods Today 1981 on netflix

A Boy Scout troupe led by their scoutmaster (Sykes) is on a field trip to a seemingly-peaceful English woodland. However, the woods are actually teeming with strange characters, some of whom turn out to be disguised police officers and others criminals. The police are searching for £2,000,000 in stolen banknotes and hope that the criminals will lead them to them. The criminals, on the other hand, are aware that the police are looking for them and doing their best to avoid betraying the location of their stash.