Gotta agree with Ross on this one. Mansions of Madness is seriously broken in favor of the Keeper. I've played as an Investigator twice, and we didn't even come close to winning either time. The second time we played, the Keeper was able to bring out two Shoggoths by the time we had moved our Investigators into the second room, and he put them right between us and all the clues we needed to find. The worst part was that there weren't any fucking weapons in the scenario! We had to fight off a Shoggoth with a revolver and a battered old six-string guitar. I think one of our characters may have actually punched it at some point.
Don't play this game unless you enjoy losing difficult games.