Two Jehovah's Witnesses have been accused of murdering 13 people on a mad "mission from God".
Vladimir Gurianov, 44, and Elvira Egorycheva 46, are said to have hacked, bludgeoned and shot their innocent victims in a nine-month killing spree.
They also robbed their victims on "God's orders". Gurianov told detectives after his arrest: "God told us to go and take the money. He said, 'Go there and take as much as you need'. So we did."
Police say the killings began after Egorycheva told Gurianov that God spoke to her in a vision and gave instructions.
Their mission took them to a city in Russia's Volga region. Egorycheva had said: "God wants us to go to Nizhniy Novgorod and cleanse the world of sinners".
A neighbour there recalled: "They were odd. He called her 'mother' or 'Princess Elena'. She called him 'my son, Prince Mikhail'."
The first victim was fortune-teller Ludmila Kostina, 51.
The next day they murdered another fortuneteller, Nina Mashtakova, 66, whose valuables they stole.
Gurianov, a convicted rapist with "mad eyes", and his partner are then thought to have stopped a 17-year-old girl.
Egorycheva told her: "Stop, sinner! I, Princess Elena and my son Prince Mikhail, have been sent by God to punish you."
Gurianov raped the girl before killing her with a hammer.
He later told police: "Mother explained every woman killed or raped by me would become my wife in the afterlife."
Gurianov later boasted of another murder. He said: "I shot at the head of this woman, but she was still alive. I shot her a second time and she fell.
"But as I was digging a grave I realised she was still alive and just watching me. So you'll understand I had to stab her."
The couple are also suspected of killing 18-year-old student Masha Maslennikova, whose body has not been found.
Other victims may include Ludmila Kotelnikova, 45, and Elena Lomteva, 37 - both discovered near their holiday homes.
One victim died when Gurianov replied to an advertisement of puppies for sale. The victim screamed as her 17-year-old son returned home: "Run, boy!"
The killers' pictures were circulated by police and they were spotted in a store and caught.
Egorycheva had a revolver, two axes, an electric shock device and a rope. A gun and a knife were found in Gurianov's jacket.
One detective said: "Our hearts bleed. They enjoy talking about what they've done. What is jail to them? If ever there is a case for capital punishment, this is it."