Starring: James Spader, Ryan Eggold, Diego Klattenhoff, Megan Boone
Chemical Mary (No. 143) - S8-E7
Factual error: French (and other nations) ATC rely on ground-based radar to track aircraft, not GPS from the cockpit of an aircraft. Meanwhile, whilst the aircraft that had been tampered with had compromised systems, the TCAS radar on the plane flying in the other direction would have alerted its pilots to take avoiding action.
Factual error: The bomb is supposed to go off at the "DC Zoo", but the scene takes place at the National Botanical Garden, on the complete opposite side of DC from where the Smithsonian National Zoo actually is.
Trivia: Red's trademark fedora was James Spader's idea.
Question: At the beginning of the final segment, the American Flag is flying upside down outside the beach lodge. Since it is pretty clear that Red would not being trying to elicit support/backup for the deeds that he and his female accomplice were about to undertake, what is the significance of this widely accepted distress signal?