In the course of a piece on the French economic wonder, the lifestyle des intermittents du spectacle, and (anti-)Americanism, Adam Gopnik writes that when "the country and its joys can be shut down by part-time trombonists ..., something is wrong, or at least ridiculous." Mr Gopnik underestimates the threat posed to global security by trombonists. In Collaborators and renegades in occupied Shanghai, Bernard Wasserstein writes of Evgeny Mihailovich Kojevnikoff, alias Eugene Pick, alias Hovans, alias Doctor Clige:
Pick's circle of more than forty paid agents, informers and associates constituted a Who's Who of the foreign underworld in Shanghai. They included the hit-man Nathan Rabin, a former member of the 'Purple Gang' in Chicago who had a sideline as a professional trombonist. An American intelligence source described him as 5' 9", strongly built, with a 'Polish face, crude expression' and a swagger. The report stated that Rabin was:
... one of the most notorious Japanese gang members in Shanghai, extortionist and blackmailer. Killer when drunk. His sole aim with the Japanese: obtain as much money as possible by criminal means and hide behind Japanese officials.
That sounds like a trombonist, and probably a part-time trombonist. The predominantly Jewish Purple Gang is usually said to have been Detroit-based, but, strangely, 333 pages of FBI files available here don't seem to mention a gangster called Rabin. And, although the post-war Oscar Rabin band is still quite well-known, principally for the sax mouthpiece anecdote, neither am I getting any ghits for a 30s Michigan-based trombonist called Rabin.
Other prominent Shanghai residents in the early 30s:

Dr Albert von MioriniAbortionist, brothel-owner, sexual extortionist
Hermann ErbenMonkey expert, narcotics dealer, "doctor"
Hilaire du BerrierShady Franco-American journalist, aviator, pimp
Don and DollyDancers
Mr Steptoe"British Secret Intelligence Service representative"
Princess SumaireNymphomaniac Indian dwarf model
"Captain" "Eugene" "Pick"Shaven-headed Cossack murderer, blackmailer, vodka drinker, drama student