When the New York Times editors hit publish on yesterday’s exhaustive report detailing how Fred Trump fraudulently funneled millions to his son — President Donald J. Trump — Showtime’s cameras were rolling. A holdover from Liz Garbus’ “The Fourth Estate” — a four part series documenting the New York Times covering President Trump’s first year in office that aired this spring — director Jenny Carchman helmed a crew that continued to follow the reporters working on this particular story about Trump’s tax avoidance, which took nearly two years to report.

The Times story by Russ Buettner, Susanne Craig and David Barstow calls into question President Trump’s image as a self-made billionaire, revealing that he received the equivalent today of $413 million from his father. Worse yet for the President, the Times reported that the money transfers were “dubious tax schemes” that sometimes involved “outright fraud.”

The film about the process,...