This is NOT a werewolf film. I wanted to make that perfectly clear from the start.
There are spoilers in this review, but for those that don't want to read them, just accept that it's a Bad film. This film isn't even bad in a way that makes it funny. It's just a bad film.
The monster is actually somekind of bug/man mutant. The explanation of how the original mutant (the boys father) became one doesn't make a lot of sense, as basically it's "man locked in celler till he was starving then fed the corpse of his lover" and that turned him into a canibilistic bug/monster who could pass on his genetic mutation to his offspring!!
The transformation was the inflating/defalting sacks under fake skin method of effects (done poorly), and it looks to have a bad cut right at the end jumping form an inflated round head bug eyed head to noticeably different looking face when it was finished. This transformation took a long time with all these poeple stood round watching doing practically nothing.
Ok, I'm going to stop here, as I really don't want to recall any more of the film. I wish I'd never watched it.
A bad movie that's fun to watch. A young married couple's night is ruined with a giant cicada (yep, that's right) get's to fulfill the husband's martial duties. Years later, their offspring goes through some major changes during puberty. Dark, depressing and gloomy fun. This is not a werewolf film, but it has the metamorphoses theme and similar plot to one.
The special makeup effects in "The Beast Within" are fantastic! Boy's physical transformation is overly creepy when his whole face bulges bigger until he's completely an monster.
I think they should do billions more special makeup effects, billions more makeup bladders effects, and lot more of the weird monster transformation special effects to make their own imaginations of making monster mutation movies and transformation horror movies.