This ecology-themed horror movie took its inspiration from the success of Jaws and moved that film's man-versus-nature conflict from the seaside to the forest. The plot of Grizzly focuses on Mike Kelly (Christopher George), a forest ranger whose peaceful tenure over a forest housing a busy nature lodge is interrupted by the arrival of a very deadly and hungry 15-foot grizzly bear. As the bear starts killing rangers and campers, Park Supervisor Charley Kittridge (Joe Dorsey) tries to cover up the problem and tries to keep Kelly from acting in a way that will cause public suspicion. Finally, Kelly decides to do what is right and teams up with macho pilot Don Stober (Andrew Prine) and eccentric naturalist Arthur Scott (Richard Jaeckel) to hunt the grizzly down on its own turf. Grizzly was roundly panned by critics for its slavish, blow-by-blow imitation of its more sophisticated model, Jaws, but its gruesome shock power made it a major hit with audiences around the world. Director William Girdler followed this success up with another ecology-themed shocker in Day of the Animals, and the film's producers made a still-unreleased sequel, Grizzly II, which provided early roles for Charlie Sheen and George Clooney.