Valentin Markin (aka "Arthur Walter") (1903 – 1934) was the chief illegal rezident and director of the espionage operations of the Soviet Union in the United States from 1933 to 1934.
He was, Chambers wrote, "a short, sturdy figure confined in a tight-fitting, rumpled suit and elevated on high-heeled German shoes."
"[2] The Russian Foreign Intelligence Service (SVR) provided the authors Allen Weinstein and Alexander Vassiliev an unprecedented peek into their archives for the preparation of The Haunted Wood (1999).
The Soviets paid "Willi" the extraordinary sum of $15,000 per year for the documents, which he passed to Markin through an intermediary codenamed "Leo," subsequently identified as New York Post journalist Ludwig Lore.
[1] According to Hede Massing, a Soviet intelligence operative who worked with Markin, he was murdered by NKVD agents due to suspected sympathies toward Leon Trotsky.