The Ghosts' Trip to Loch Ness

When Henry and his friends learn that the Loch Ness monster has been sighted, they take off for an adventure in Scotland. They spend most of their time on the lake taking pictures and hoping to glimpse the monster, but they never see even a flick of its tail.
When the ghosts return home and have the pictures developed, they’re in for a surprise--the monster was with them the whole time!