Haim Bodek built his own high-frequency trading firm in 2007, wrote an algorithm he believed was faster and smarter than the competition, and watched its profits mysteriously vanish. Rather than write off the loss, he starts digging into the market's plumbing, and what he finds turns him into what traders call the Algo Arms Dealer: an insider willing to explain, on camera, how modern Wall Street actually works. Trading floors have been replaced by server farms running algorithms that execute trades in fractions of a second, and Bodek argues the resulting system is so fragmented and fast that almost nobody overseeing it, regulators included, fully understands it. Director Marije Meerman closes out the trilogy she began with Quants: The Alchemists of Wall Street and Money & Speed: Inside the Black Box, again using the people who built high-frequency trading to explain what it has become. Bodek's decision to go public with his findings sits at the center, a rare case of someone inside the machine deciding to describe it plainly.