Case of the Purloined Painting

When an American Army unit arrived at the end of the war, some soldiers appropriated items in what appeared to be abandoned circumstances. A small painting by a mid-level Polish painter is used by an ex-GI to float a bank loan which results in the founding of a manufacturing firm in Minneapolis. Now the painting and the ledger become the center of murderous attempts by the descendants of the veteran to conceal the painting's journey. World-wide efforts at repatriation of stolen art from WWII is a major ongoing effort and the story links to that effort as international operatives descend on the Twin Cities. Enter private detective Sean Sean. He is a short but effective operative who, unlike many PIs of the modern era, doesn't sleep around, doesn't shoot people unnecessarily, and has many friends among various local law enforcement agencies