If the threat were not so real, you might think the whole story was an overblown plot in a comic book.

Over the weekend, the world came under attack by nefarious but clever villains who used computer malware to force the cancellation of surgeries in England, throw off train schedules in Germany, interrupt movies in theaters in South Korea, close gas stations in China, shut down auto factories in France, and disrupt daily life in thousands of small and larger ways in more than 150 countries.

OPINION

It was the stuff of the Joker or the Riddler, if the threat had only ended there.

“Oops, your files have been encrypted!” read the taunting message on hundreds of thousands of computer screens. The hackers demanded a ransom, usually a modest $300 to start in untraceable bitcoins.

But the virus, called WannaCry or WannaDecryptor, is expected to spread this week, and security experts warn it could be refined by copycats to remove a “kill switch” that has slowed its growth.

Even if no further damage is done, the weekend attacks remind the modern world how vulnerable it is to cyberattacks, and of the need to be hyper-vigilant about security. Many victims of the attacks had failed to update their security systems, though they had been advised to do. Or, as in the case of companies in China, they were using pirated software that included no updating services. They were like storekeepers who leave a window open, inviting burglars.

The attacks raise questions as well about the way many nations stockpile such dangerous viruses, the way some nation’s stockpile nuclear bombs. It is suspected the computer code to create WannaCry, a kind of virus called ransomware, was stolen from the National Security Agency.

Domestically, it is the job of the FBI to investigate computer hacking. All the more reason, then, after this weekend’s cyberattacks, for President Donald Trump to appoint a new director of the FBI who is a seasoned and politically independent  pro and not a White House lapdog.