Spirits of the dead return to our world during Japan’s Obon holiday, and it’s no wonder that August is the time for telling ghost stories.

Japanese go back to their hometowns to greet these visitors from the spiritual plane and to scrub the family grave. While walking by a local cemetery in Shimabara, I noticed some families had erected large paper lanterns at their graves.

This is hatsubon 初盆, the first Obon for those who have recently passed away. Two people holding graveside vigil by their lantern were busy staring at their smartphone screens. Here in Nagasaki, small fireworks are set off in cemeteries in a tradition called yabiya. Check out the video below.

Meanwhile, Buddhist priests make the rounds on their scooters, black robes flowing in the wind. One came to my in-laws’ to say prayers at the lantern-lit butsudan altar, which holds the memorial tablets (ihai) of dead kin. The sutras chanted, he left in a cloud of incense.

I haven’t spent much time at the butsudan apart from the requisite paying-of-respects prayer when we arrived. There was also the issue of mice coming from a nook behind it during the heavy rains in July when they sought refuge from the deluge. But I digress…

Anyway, we’ve been sleeping on futons in a room by the butsudan and the other night we hit the tatami as usual. Something woke me up around 2:30 a.m. and I noticed the light over the butsudan was on. The house was silent and everyone else was asleep. Who could have turned it on?

I thought someone might have entered the house, but the dog hadn’t barked. I looked at the butsudan light, an old-school chunky switch. Was there a timer? No. I switched it off and tried to get back to sleep.

In the morning I asked around: Had anyone turned on the light? No. Very odd. Could the switch have been in the on position and then activated long after due to temperature changes or something? Apparently not. The fluorescent tube flickers on every time I flip the switch.

My mother-in-law dismissed all this with a laugh: “It was just the spirits of grandma and grandpa saying, ‘We’re going back to the other world now!'” I hoped so. But I wasn’t sure what I’d do if the light came on again in the middle of the night.

And of course, it did.