Identical apartment blocks line up like dominoes along the Avenue of Science, a sleepy St. Petersburg street with a grandiose Soviet name.

On a chilly evening last spring, when the trees had yet to bloom, this residential street became the scene of a brutal murder. A wiry young man arrives on foot, having walked the last three miles to avoid detection by the security cameras on public transport.

He approaches a well-preserved Soviet-era apartment block, the home of Dmitry Tsilikin, a renowned St. Petersburg journalist. Dmitry has been expecting him.

When the young man leaves later that evening, he takes Dmitry’s phone, laptop and keys and locks the door behind him, leaving the 54-year-old journalist trapped and bleeding to death in his own home. He had been stabbed over 30 times.