Although she looks harmless, 68-year-old Chisako Kakehi is probably one of the most dangerous women in the world. Nicknamed ‘The Black Widow of Kyoto’ by the media, she is believed to be responsible for the deaths of eight men who were romantically involved with her at some point in time.

Kyoto-based Kakehi is currently in police custody, for the fourth time in her life. According to Kyoto police, Kakehi has been in relationships with over 10 men, eight of whom eventually ended up dead. So far, she has been charged with the murder of a former husband in Kyoto and a boyfriend in Osaka, as well as the attempted murder of a man in Kobe.

Kakehi first became known to the police in December 2013, when her 75-year-old husband was found dead in their home in Kyoto. The death was initially believed to have been caused by a heart attack, and Kakehi perfectly played the part of grieving widow. But police soon began to discover gaping holes in her story. She was married to the man for only a month, and she stood to receive a huge inheritance after his death. Later, traces of lethal cyanide were discovered in the dead man’s blood.

So the police launched a full-fledged investigation regarding Kakehi’s involvement in the crime. It was during the course of this investigation that they uncovered a chilling truth – several of the men she had previously dated or married had died of cyanide poisoning. And she conveniently happened to be the sole beneficiary on all their wills.

The first time was in 1994 – her first husband had passed away at the age of 54. She then met a man through a dating service and married him, and he died of a stroke in 2006, at age 69. Her third marriage also ended with the death of her 75-year-old partner, in 2008. Husband number four suddenly fell ill at home after only two months of marriage, and was confirmed dead on arrival at the hospital.

A boyfriend was the next to go – he was believed to be suffering from cancer when he died in 2012. She was then engaged, but (surprise, surprise), her fiance died after he collapsed while riding a motorcycle. In 2013, her 75-year-old boyfriend collapsed in the parking lot of a restaurant, shortly after the couple had shared a meal. The eighth and final death was of her 75-year-old husband, the one that finally got her caught.

At first Kakehi insisted that she was innocent. “I don’t even know how to kill someone,” she said. “And I don’t know where the cyanide came from. I wish someone would tell me.” But the police soon discovered her very own stash of hydrocyanic acid, stored in a planter in her home.

According to Japanese tabloid Flash, Kakehi used matchmaking websites to approach her victims. “She came across as a normal, kind person, and someone who has overcome many problems,” a dating service told the magazine. “Since so many men have been duped, it is clear that she is a manipulator.”

The police are yet to establish her motive, but the obvious answer right now is money. She is currently the sole beneficiary of 800 million yen in insurance money and other assets.

Sources: Broadly, Tokyo Reporter, One Way Japan