“Money Monster,” the Jodie Foster-directed film following a bombastic financial news personality, a corrupt Wall Street and the ensuant hostage situation, isn’t the story the screenwriters originally set out to tell.

When screenwriter Jamie Linden (“We Are Marshall” and “Dear John”) sat down with Worth Wray — an economist and global macro strategist at Avidian Wealth Management — in a San Diego cafe, he wanted to know why markets have changed and what’s going on in the Byzantine world of high frequency trading and financial markets.