The episode is one of the few in Part 1 shows what Zenigata looks like without his hat. His hair is neatly styled into a combover and he has a widow's peak.
The words in the letter to Zenigata are actually lyrics to 'Bonjour Paris' by Francis Lemarque.
The episode's ending, where Lupin escapes prison to see Zenigata off on the plane, recalls the ending of the Arsène Lupin vs. Sherlock Holmes story where Lupin sees Holmes off on a train after the latter thinks he's outwitted the former.