Gig Young and Carol Lynley star in this lethargic H.P. Lovecraft adaptation as a couple who inherit a rundown mill in a small coastal town. They go to check it out with the intention of turning it into a summer home. Once they get to the town, they are almost immediately harassed by the scuzzy locals (led by Oliver Reed) who want to get into poor Carol's pants. Carol's got bigger fish to fry as there is a mysterious person/thing in the titular room who's crazier than an outhouse rat that can't wait to do some damage to the unfortunate pair.
As low budget Lovecraft adaptations from the 60's go, this ain't no Dunwich Horror. Lovecraft was a master at stringing his readers along until the shit hit the primordial fan. What's pretty infuriating about this movie is that it strings us along for so long that when it finally goes to deliver the goods, it completely drops the ball. The "explanation" of what is actually in the shuttered room is terminally lame and is pretty stupid to boot. (The dopey ending will especially put a sour taste in your mouth if you are a die hard Lovecraft fan.)
Lynley is thoroughly bland in the lead and Gig is painfully miscast as the upstanding husband. I did get a kick out of seeing Reed overacting to the hilt as the lecherous local though. I just wished that him and his crew of miscreants (who play a demented variation on water skiing, except they use a pickup truck) were a little more crazier. As it is, the flick just feels like a PG version of Straw Dogs with the crazy lady from Pet Semetary tossed in there for no good reason.