When Hollywood brought "The Big Short" to the big screen, the book's author, Michael Lewis, was as surprised as anyone. A film about debt going bad? Seriously? But in filmmaking, as with investing, timing is everything. What makes the movie so timely is its role as primer for what's afoot in China.

There's little about China in Lewis' 2010 best-seller. And, frankly, the Brad Pitt-starring screen version can feel dated given the cacophony of world events since Wall Street's 2008 drama. That is, until you consider the $23 billion dilemma now facing Beijing, and, by extension, the hedge-fund dynamics Lewis chronicled.

This column has examined China's $28 trillion problem, which relates to its post-Lehman Brothers credit explosion. A more immediate one is the roughly $23 billion of offshore debt rated just one small step away from junk by major credit-rating companies. The second biggest economy has a devilish assortment of so-called fallen angels. Any sudden rash of downgrades could trigger the next bout of turmoil in global markets.