Sure, any behemoth is bound to cause trouble. But then there's The Giant Behemoth, a 1959 British version of the American monster film The Beast from 20,000 Fathoms. It's a less energetic film, the effects aren't as good. I do like the performances better in The Giant Behemoth but for the most part you're better off watching The Beast from 20,000 Fathoms.
The Giant Behemoth starts off nicely with a father and daughter (Henri Vidon and Leigh Madison) returning to shore with a boat full of fish. The setting is a beach in Cornwall and we get a nice little introduction to the town when the daughter goes to the tavern looking for her father and is shocked to find he isn't there bragging about his catch. It's the first of several occasions where the giant behemoth proves a master of the stealth kill.
But most of the film sticks with the scientists--a serviceable Gene Evans and an impressively grave Andre Morell who elevates the material quite a bit. There's also a memorable scene with Jack MacGowran as a palaeontologist getting increasingly excited as he realises these men are telling him there's a real live dinosaur walking around.
We don't see the beast for most of the film and until the last ten minutes or so he's little more than a neck and head, shot in live action, reminding me of the Loch Ness Monster in Terror of the Zygons. When the budget allows stop motion to kick in for the climactic scenes, it's not as good as Ray Harryhausen's work on The Beast from 20,000 Fathoms but Willis O'Brien--who did the effects work on the original King Kong does create a long necked, massive reptile with personality. I liked the close ups of his head swaying back and forth.