Mikhail Novosyolov was born in Sarapul, a city in the Udmurt Autonomous Soviet Socialist Republic, which was part of the Russian Soviet Federative Socialist Republic. 

Mikhail Novosyolov committed a series of murders between 1977 and 1995, resulting in the deaths of 22 people. His victims were between the ages of 6 and 50 and included both young children and adults. He killed 16 individuals in Russia and 6 in Tajikistan.

His first murder took place in Chaykovsky, Perm Krai. He targeted a random girl. After killing her, he initially fled but returned a few hours later to commit sexual acts with her body. Novosyolov was able to gain the trust of his future victims, pretending to be skilled in various professional fields. He typically killed by striking victims with a heavy object, then choking them, followed by sexual acts with their bodies.

In one unusual case, he lured a girl and a boy by promising them chewing gum. He killed them using a sharp electrode hidden under a bicycle's saddle. Their bodies were later disposed of in an aryk, which is a type of irrigation ditch.

Authorities took a long time to connect his crimes because he moved between different towns, committing murders in several places. His use of three different passports with various names helped him impersonate others and evade suspicion.

When an all-Russian search was announced for him, Novosyolov traveled to Tajikistan. There, he started working at a psychiatric hospital in Dushanbe. He was arrested while attempting to steal an air rifle in a local park. After being detained, police soon discovered he was being investigated for multiple murders related to rape and the attempted rape of minors.

During his interrogation, Novosyolov confessed to three additional murders in Tajikistan and admitted to committing 16 murders in Russia across various regions including the Volga, Ural, and Siberia. He provided details that led authorities to the burial sites of some of his victims.

After the investigation, Novosyolov was declared insane and was sent to civil commitment.