This film's idea of a reviving ancient flesh when in contact with water is truly original, its sordid atmosphere is very well achieved and Peter Cushing and Cristopher Lee's presence give it a sort of category in the genre. In fact, when Cushing arrives back in England with a strange scary huge skeleton from New Guinea and you learn that water could bring it back to life you have the feeling you'll watch a most interesting horror picture focused mainly in that strange fact.
But then other story appears about Cushing's insane wife's death and their daughter's obsession with her mother that turns into a parallel plot. And that's when "The Creeping Flesh" looses quality and sense -in its genre of course- and things start to mix up badly; there is also a mad killer at large (not frightening at all). What I mean is that so many different topics -unrelated between them- is too much for just one film, and the final outcome is not a good product. Besides, the special effects of the Papuan monster came to life are poor, even for 1973.
Perhaps a better product would have come out if the film had stayed with just the archaelogical evil creature, but it seems the writers couldn't find a way to develop the subject and make a full script out of it.
The picture has some good moments, but in my opinion it is just for Cushing and Lee's fans and no more than that.