Theater Review: Among all the honest and knowledgeable financial traders in America, there are greedy wolves waiting in the background to pounce and seduce investors into their schemes. La Jolla Playhouse’s world premiere of “Junk: The Golden Age of Debt,” by Ayad Akhtar and directed by Doug Hughes, tackles the topic with intrigue and humor. It’s 1985 and the wolves are out there to scam whomever they can. Enter Robert Merkin (Josh Cooke) shadowing the real-life Michael Robert Milken, a former financier and philanthropist convicted in 1989 of racketeering, securities fraud and insider trading. Merkin plans to use investors to take over a devalued conglomerate and then maneuver the stock through junk bonds. Cooke pulls off this character with the gravitas of a push-to-the-end bond trader.