Even if you think he is cute he wears a very bad mask, or else is invisible for most of the film.
He is a brilliant, vain, jealous, workaholic who had no time for his girlfriend so she dumped him. This makes him into a sexually frustrated pervert. Then he gets made invisible and the serum turns him into a crazy serial murderer. He's hardly a likeable character.
I thought about half way through that it showed some signs of getting better, but once they all got locked underground and he began to pick them off, one by one, it just became a typical slasher movie.
Great special effects but poor science -- for example in the freezer the temperature fell below -30°C yet she is picking up iron bars with her bare hands!
Why didn't she just stick the bar into the evaporator fans anyway?
And how could that little nitroglycerine exposion send the lift so high up the shaft but not blow them off the ladders?
I don't know what you mean by "ruddies" but there is a fair amount of breasts and nipples!