This is an awesome movie. It is the best & original Classic Film Version of "The Lost World". Based on Sr. Arthur Conan Doyle's Novel by the same name. Which was about Dinosaurs & Prehistoric Creatures still alive in the upper reaches of the Amazon in South America. The film version is pretty much the same but to bring the dinosaurs to life is a whole other story. That job went to Special Effects Pioneer Willis H. O'Brien who would later gain world wide recognition with his ground breaking Stop-Motion Animation in The Classic "King Kong" (1933). Known to the modern world as The Godfather Of Stop-Motion Animation. O'Brien was a true pioneer. He brought Dinosaurs to life in an earlier Silent Movie Short called "The Ghost Of Slumber Mountain" (1917). His earlier Silent Movie Shorts when he first conceived the idea were corky & primitive but still entertaining today. His early starting projects for Edison used Clay Animation. Movie Film Shorts "The Dinosaur And The Missing Link: A Prehistoric Tragety" (1915), R.F.D. 10,000 B.C. (1916), & Prehistoric Poultry (1916). Later projects the first & bigger project would not use clay. Metal Skeletons connected by Wooden or Metal Ball & Socket Joints. Very movable & flexible. Made to hold a one frame pose for an exposure to be slightly changed to the next & next. The Lost World (1925) I think was O'Brien's best work most of it except for few jerky Dino Animation Sequences. I don't even think that was O'Brien's Stop-Motion. Fred Jackman helped out with animation. Which he did the jerky animation scenes u see. Marcel Delgado who constructed the dinosaur models did an excellent job. The movie is a Masterpiece of early Special Effects I especially like when the Brotosaurus escapes the cage & breaks loose terrorizing the streets of London that is very memorable. The movie is in my Top 10 Favorite Films of all time. Check it out if you haven't already you Stop-Motion Fans & Dinosaur Movie Fans. I just recently got the Image Entertainment DVD Version which restores more then 50% more of the film which originally was 100 some mins. Now they have 92 mins.& has some extra features. I also have the Lumivision DVD of the 64 min. version that has trailer & those early Edison Clay Animation Shorts & 1 other Clay thing about Dinosaurs that O'Brien didn't do though like The Edison ones. Last it has Still Galleries & Notes by Ray Harryhausen plus one last thing Promotion Piece about The Lost World Puzzle. I would advise both but buy the Image Entertainment DVD Version though if you wanna really enjoy the film.