Children across South Shropshire, North Herefordshire and Worcestershire are being encouraged to talk to their parents if threatening messages pop up on YouTube clips of things like Peppa Pig and Fortnite.
The disturbing content - known as the 'Momo challenge' - orders the viewer to self-harm or worse.
It has already been linked to the suicide of a 12-year-old girl in Argentina and at least 130 teen deaths across Russia.
And now, UK primary schools have warned about the dangers of the game, saying it presents a "serious risk" to kids' safety.
Matthew Smith from the suicide prevention charity If U Care Share wants host platforms to do more: