Scooby-Doo/Scooby-Doo and the Loch Ness Monster
From The TV IV
Scooby-Doo and the Loch Ness Monster is the seventh in a series of made-for-DVD animated movies starring the cast of Scooby-Doo. It was released June 24, 2004.
The gang is in Scotland visiting Daphne's cousin Shannon and to attend the Highland Games when Blake Castle is rattled by the mythical Loch Ness Monster. A scientologist and an author come to ideological loggerheads over the Monster's existence, so it's up to Scooby and the gang to make sense of it.
This is the third time that Scooby and the gang dealt with a mystery about the Loch Ness Monster. They previously dealt with a faux Nessie (in a New England lake, of all things) on The New Scooby-Doo Movies in 1972 (The Loch Ness Mess, with the Harlem Globetrotters) and in 1977 (A Highland Fling With A Monstrous Thing).
Followed by Aloha, Scooby-Doo.