The `plot' of this film contains a few holes you could drive a massive truck through, but I reckon that isn't always top priority in horror. Two elderly sisters in rural England keep their brother in the cellar since more than 30 years. Now, he escaped and started a killing spree, focusing on militaries that are homed nearby. `We only did we thought was best for him' they keep on repeating and  strangely  all the army officers love these women and don't doubt their sincerity, even though 5 of their men died. I don't know whether to find the revelation near the end suspenseful  or tedious! In a way, this film reminded me about `Arsenic and Old Lace'. In that black-comedy classic, two half-insane siblings mother their goofy younger brother as well, yet they do the killing there. The old ladies in `The Beast in the Cellar' are by no means less crazy, though. The `horror' in this early 70's film is very amateurish and cheap, but there are a few neat attempts to build up the tension. Too many `old-ladies' talk about the good ol' days, though and that rarely is something you seek in a horror film with such an appealing title. Flora Robson, who may be recognized by classic film buffs, plays one of the sisters. She gave image to the Queen of England is the legendary Errol Flynn swashbuckler film, the Sea Hawk.