On a weekday afternoon the bullet train from Tokyo to Osaka is normally full of dark-suited businessmen, the in-carriage sound a mix of tapping laptop keys and the outside air rushing by at 300km per hour. But last Friday, the men appeared to have been elbowed aside by a small army of harried housewives ferrying infants and children, their cries and horse-play turning the train into a speeding kindergarten.
Among the thousands of women who have fled west, south or out of Japan altogether over the past week was my pregnant partner. On Wednesday, after two days of mounting alarm about the state of the Fukushima nuclear complex 250km north-west of Tokyo, I persuaded her to get on the south-west bound Osaka train. She didn't want to go. Like millions of others, she faces a bitter choice. Staying means exposing herself and our unborn child to low-level contamination, with the threat of worse to come; abandoning the city means leaving behind her family and friends.
But how much radiation is bad for you? This is the daily topic of conversation for millions of people in the world's largest metropolis. Most fear the worst after half a century of cover-ups, lies and bad science-fiction movies, but while contamination in the Tokyo area is elevated, few experts suggest it is truly harmful to human health – at least not yet.
A government spokesman sought to calm fears during the week with his widely disbelieved claim that even life within the 20km evacuation zone around the irradiated Fukushima complex is not that dangerous, saying: "The radiation is not high enough to affect the human body over several hours or even days." He is not the only one who believes the media is scaremongering. One of Japan's best-known foreign TV personalities posted a video on YouTube last week pleading with overseas media to "stop stirring up hysteria". "You're freaking out the foreign community, and it is taking people's efforts from where they need to be ... up north," said Daniel Kahl. Possibly he had in mind The Sun, which this week quoted British ex-pats saying Tokyo had become a ghost town resembling a zombie movie, with no food, fuel or water.
This was news to most residents of the city, where, despite power cuts and shortages, millions have been going to work, shopping for food and drinking in bars.
Whatever the truth, thousands of foreigners have put their families on trains to the west or south, or on planes to Europe, Asia or America. Many have quietly taken holidays from work and run for the airport. Even those who believe, perhaps foolishly, that Tokyo's air is still harmless and that the Fukushima crisis will be resolved, have succumbed to relentless, sometimes hysterical pressure from relatives at home.
Most of us have little confidence in the firm running the plant, or in Japanese media reassurances. But how to judge? When I joined my partner in Osaka on Friday, she was feeling abandoned: "How can I stay here, with you and my family in Tokyo?" So we will head back to the capital and its dark cloud of uncertainty.
The exodus of foreigners is in stark contrast to the stoic resignation of the Japanese. Suited salarymen go to work as normal. Housewives queue for bread, water and petrol. Many foreign commentators have already noted this admirable Japanese ability to carry on as the scenery collapses around them.
Yesterday our jangled nerves were rattled by another quake, more rumours of a radiation spike and the news that efforts to cool Fukushima's reactors were failing. In the midst of all this came a call from the young woman at my local video rental store reminding me I had forgotten to return a DVD borrowed before the world shifted on its axis last Friday.
It was surreal but oddly reassuring that someone is worrying about fines for overdue movies even as the world goes to hell in a handbasket.