I saw a month or two ago in an Italian paper that the Villa Cascana, in which I once stayed, had been pulled down, and that a manufactory of some sort was in process of erection on its site. There is therefore no longer any reason for refraining from writing of those things which I myself saw (or imagined I saw) in a certain room and on a certain landing of the villa in question, nor from mentioning the circumstances which followed, which may or may not (according to the opinion of the reader) throw some light on or be somehow connected with this experience.The unnamed narrator of Benson’s short had planned the perfect getaway, a relaxing sojourn at a tidy, Italian villa. But the moment he crosses its threshold, he senses something’s amiss in the cool marble halls. No amount of good news from home or pleasant conversation with the proprietor can dispel his misgivings. But when a bout of insomnia robs him of sleep one night, and he goes exploring, he stumbles across a heart-stopping sight: an unoccupied room swarming with massive, mottled, slightly luminescent caterpillars.
The Villa Cascana was in all ways but one a perfectly delightful house, yet, if it were standing now, nothing in the world -- I use the phrase in its literal sense -- would induce me to set foot in it again, for I believe it to have been haunted in a very terrible and practical manner. Most ghosts, when all is said and done, do not do much harm; they may perhaps terrify, but the person whom they visit usually gets over their visitation. They may on the other hand be entirely friendly and beneficent. But the appearances in the Villa Cascana were not beneficent, and had they made their “visit” in a very slightly different manner, I do not suppose I should have got over it any more than Arthur Inglis did.
The story rolls along conventionally enough right up until the very end. As expected, another occupant of the villa discovers one of the caterpillars and commits a careless transgression that escalates the horror. But instead of a final act stained with gore and grue, the denouement tapers off quietly, which makes it all-the-more frightening. The inhabitants of a world with cell phones and air conditioning and antibiotics have a hard time comprehending a spiritual world at all, much less one bent on harm. But they understand the 2 a.m. phone call and the awful news delivered in hushed tones.
Instead of the sucker-feet of ordinary caterpillars they had rows of pincers like crabs, and they moved by grasping what they lay on with their pincers, and then sliding their bodies forward. In colour these dreadful insects were yellowish-grey, and they were covered with irregular lumps and swellings. There must have been hundreds of them, for they formed a sort of writhing, crawling pyramid on the bed.
Occasionally one fell off on to the floor, with a soft fleshy thud, and though the floor was of hard concrete, it yielded to the pincerfeet as if it had been putty, and, crawling back, the caterpillar would mount on to the bed again, to rejoin its fearful companions. They appeared to have no faces, so to speak, but at one end of them there was a mouth that opened sideways in respiration. Then, as I looked, it seemed to me as if they all suddenly became conscious of my presence. All the mouths, at any rate, were turned in my direction, and next moment they began dropping off the bed with those soft fleshy thuds on to the floor, and wriggling towards me.
“Caterpillars” is in the public domain, and you can read the full text at HorrorMasters.com. Also, if you’re inclined toward audiobooks, you can download a very adequate reading of the story at LibriVox.org.