October has long been considered "horror month," with a flood of horror books, TV shows, DVDs and Blu-rays all timed for release during the scariest 31 days of the year. This past weekend was no exception at the box office, as no less than four horror movies competed for attention ... but surprise, surprise, all were left gasping for air.

'Let Me In' and 'Case 39' both opened wide on more than 2,000 screens, yet only drew about $5.3 million each, about half of what was expected. The under-publicized 'Chain Letter' showed up on 400 screens, making just $352 per screen for a total of $143,000, while the unrated 'Hatchet 2' managed to average $912 at each of its 68 screens, totaling $62,000. Looking back over the past seven weeks, 'Piranha 3D' underperformed somewhat ($24.8 million so far), while 'The Last Exorcism' ($40 million) did better and 'Devil' ($27.4 million) about the same. If horror movies are dying at the box office, what does that mean for the upcoming releases of 'Paranormal Activity 2' and 'Saw 3D'?