There is no place on Earth where a person can say with absolute certainty they are not being stalked by ninjas. Logic suggests this is unlikely but logic also dictates that you can't prove a negative - and the art of the ninja is to go unperceived.
It is particularly difficult to discount the possibility of sudden, gurgling death while walking alone in the woods of Togakushi, among 900-year-old cedar trees, around the edges of a village that was once supposedly home to a martial community of these legendary super-sneaks and master killers.
The area is not as remote as it used to be. Now contained in the Joshinetsu Heights National Park, it is at the foot of two volcanoes in the Japanese Alps to the north of Nagano.
Buses from this city run on the hour and take only 45 minutes to reach the last stop on the Togakushi Birdline Highway - a scenic, bracing, horrifying drive upward through a coil of switchbacks, hairpin bends and mountain passes, with the road covered by black netting to protect vehicles from falling rocks and ninja ambushes (such attacks are admittedly so rare as to occur only in the minds of excitable travellers).
It is not yet spring but the snow is starting to melt at this altitude. When it does, thousands will come to view the cherry blossoms and many more will arrive later in the season to see a million rainbow-coloured cosmos flowers bloom on the slopes of Mount Kurohime, or to watch the wild birds in the Togakushi Forest Botanical Garden, or take part in the annual soba festival. Every prefecture in Japan boasts at least one delicacy people will cross the country to taste and these mountains have become known above all else for soba noodles.
Even at this dormant time of year - and in the middle of a rainstorm that would suit the final scene of a Kurosawa movie - a queue has formed outside the famous Uzuraya restaurant at Chusa Miyamae, where I get off the bus.
The diners inside are hidden behind clouds of steam but one of the chefs must have seen me join the line for lunch without an umbrella. He brings one out to me as a gift, apologising for the weather and the wait.
The noodles eventually prove to be worth it, the buckwheat beer might well be nourishing - but this is not what I came for. I'm not here to see the shrines either - there are three in the vicinity, along with several sub-shrines, each one deep in the forest and dedicated to a different Shinto god - which also draw visitors and worshippers to Togakushi.
The highest of these, Okusha, honours the unpronounceable deity Amenotachikaraono- mikoto, whose power is said to be manifest in the mystic aesthetic of the surrounding peaks, lakes and trees. With all due respect to him and the serenity of his domain, my own pilgrimage takes me in the opposite direction, towards the Ninja Village.
The few people I meet on the path - none of them foreigners - seem to find my choice amusing. For one thing, modern Japanese tend to believe that ninjas have never existed outside folk tales and pop culture. For another, this particular tourist attraction has been designed primarily for children. But I have come this far to honour my own childhood masters.
I've been preparing since I first became aware of these shadow-warriors through illicit rented videos such as Sakura Killers and Revenge Of The Ninja, at the age of eight or so. From that point on, I resented the fact that I had not been born in feudal Japan, nor trained since birth in the harsh and esoteric skills of an assassin.
My parents possessed their own subtle arts and used my fixation against me. "A ninja wouldn't whine like that," counselled my father when I objected to something or other. "The ninja is always adaptable." My mother, to be fair, bought me the ninja paraphernalia - mostly screen-printed jumpers and sew-on badges that briefly earned me the school nickname of "ninny". But she drew the line at grappling hooks, throwing stars and, most specifically, the kusarigama, a retractable combat scythe on a metal chain with a heavy iron weight at the end.
I find all these tools and weapons on display in the Ninpo Shiryokan, a small, thatched museum at the centre of the village. I appear to be the only visitor and the only sounds are the rain on the roof and the creak of a wooden water-wheel. A true ninja would probably expect a trap and would definitely not get a fright when two life-size ninja mannequins seem to materialise out of nowhere in the darkest corners of the room, staring from the rafters through black hoods and black glass eyes.
Photographs on the walls show real-life ninjas doing all the things they're famous for: fighting with swords and metal claws (as well as those wickedly contentious kusarigama), deploying smoke bombs and blowguns, running up trees, breathing underwater, scaling castle walls and vanishing so far into the background that their presence is revealed only by outlines drawn in highlighter pen.
Almost every exhibit has been donated by Soke Masaaki Hatsumi, the living custodian of a ninja tradition that he and his followers claim originated here in Togakushi more than 800 years ago, when the village was known as Togakure, or "concealing door".
Elderly but still adept, Hatsumi has become a sort of Dalai Lama to latter-day practitioners of "ninjutsu", now an abrupt, emphatic form of self-defence that he teaches from his base in Noda City.
According to the various books he has written, ninjas were never quite the spies and assassins portrayed in movies, comic books and video games but rather an "illegal counter-culture" of poor but hardy mountain people who trained themselves to evade, resist or withstand opposing forces: bandits, the elements, the samurai. If the evidence for this is scant or contradictory, he has explained, it is precisely because "the origins of their art were shrouded by centuries of concealment and deliberate confusions of history".
Good or evil, historical or mythical - these are not the questions that concern me as I pay the old man at the gate to the Shinobi Karakuni Fushigi Yashiki, which literally means Ninja Gimmickry Wonder House.
I'm asking myself how quickly and quietly I'll be able to steal through this maze of trick rooms, hidden passages and secret chambers. As it turns out, I'm as stealthy as a Christmas goose and less physically adroit than Winnie the Pooh.
After more than an hour of slipping awkwardly on false floors, scrabbling at invisible exits and getting stuck half-way through ceiling panels, with my legs pedalling in mid-air, I find myself in a room from which there is no escape. The painting on the wall does not conceal a tunnel and yanking on the candlestick has no effect. This is funny for a while, then disconcerting and finally chastening. I'm missing something, both literally and profoundly.
Perhaps I don't possess an inner ninja and if I do, he is prone to rationalising. He reassures me that a ninja delights in confusion.
Even his own? Especially his own! And would a ninja yell for help or accept this playhouse as his tomb? Before I can decide, the old gatekeeper shows up, laughing between missing teeth as he slides an entire wall aside to show me the way out. Surely, I ask myself, this constitutes what the Japanese call a loss of face?
My inner ninja tells me that's why he wears a mask. The old man must understand, because he offers me a handful of throwing stars. And when four out of seven of these arcane weapons find their targets in the watchful sugi trees of Togakushi, I choose to interpret his smile as recognition of lethal potential, rather than indulgence of yet another Western tourist for whom Japan will always be a largely imaginary place.
FAST FACTS
Getting there
Malaysia Airlines flies to Tokyo for $888 (low-season return from Melbourne and Sydney, excluding tax). The best way to reach Togakushi from Japan's major cities is by Shinkansen bullet train to nearby Nagano, followed by an exciting bus ride up the Birdline Highway. Buses leave hourly from 7am-7pm at Kawanakajima station, directly opposite Nagano train station - ¥1350 ($20.50) one way, return ¥2400. Chusha is the last stop. The ninja museum and village, Togakure-ryu Ninpo Shiryokan, which includes the wonder house, is open 9am-5pm (closed November to mid-February). Entry is ¥500; phone +81 26 254 2395.
Staying there
Togakushi Kogen Yokokura is a traditional ryokan in the centre of the village, with a French-style cafe. As with many such establishments, it does not accept online bookings but the owner speaks some English. Double rooms from ¥7000; phone +81 26 254 2030. Just north of town, Pension Garnie is a little more expensive and Westernised. Rooms from ¥15,000; phone +81 26 254 3130.
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