What Lies Below is touted as a cross between Species and A Quiet Place and is written and directed by Braden R Duemmle (remember my Red Flag that seeing the same name in both those roles tends to point to a lack lustre end result).
The plot follows a mother, Michelle (Mena Suvari), and her teenaged daughter Liberty (Ema Horvath). Liberty returns home to find that her mum has a new boyfriend, the seemingly perfect John Smith (Trey Tucker) ... but as the film unfolds, so John is seen to be creepy as heck, and possibly not even human!
The only nod to Species here is that John is looking to procreate (and in a couple of scenes he has freaky alien feet), and A Quiet Place? No idea where they got that one from. The film drags its length as it's fairly apparent that they had no budget for any effects, CGI or otherwise, and so you're waiting for things to happen, to be revealed and they never are ...
It's also a Red Flag when the various websites which offer 'explanations' of plot points and endings are all over a film, as it simply tends to mean that the film has done a poor job of explaining them in the narrative they are presenting. And sure enough, there are lots of sites explaining 'the boat scene' and the ending of this film.The film looks nice, and the performances are okay, though everyone seems to be the wrong ages, and the scenes of John watching Liberty shower, and then later on the attempted impregnations are a little too far on the side of the voyeuristic and inappropriate. So watch it if you like a slow burn film ... some interesting ideas ... but don't expect it all to make total sense ...
And the title? What exactly does lie below? Are we talking about under the lake here, or is this a euphemism for what John keeps in his shorts ... we shall never know!