* Sylvia Syms also appears in Episodes #29 "The Noble Sportsman", #99 "The Best Laid Schemes" and #109/110 "The Fiction Makers"
* Robert Cawdron also appears in Episodes #4 "The Covetous Headsman", #19 "The Work of Art", #64 "The Abductors" and #90 "To Kill A Saint" (all: same role)
* Manning Wilson also appears in Episode #19 "The Work of Art"
* The character of Inspector Quercy appears several times in the series although played almost every time by a different actor. It's Eugene Deckers in Episodes #4 "The Covetous Headsman", Manning Wilson in #19 "The Work of Art" and #42 "Jeannine" and John Serret in #64 "The Abductors" and #90 "To Kill A Saint"
* Martin Miller also appears in Episode #66 "The Smart Detective"
* Peter Elliott also appears in Episodes #30 "The Romantic Matron" and #79 "The Man Who Liked Lions"
* John Dearth also appears in Episode #5 "The Loaded Tourist"
* Peter Diamond also appears in Episode #30 "The Romantic Matron"
* Michael Anthony also appears in Episode #88 "The Death Game"
* Maggie Wright also appears in Episodes #41 "Lida", #61 "The Crime of the Century" and #90 "To Kill A Saint"
* There seems to be some confusion about Sylvia Syms' role name - she is called both "Roger" and "Rogers" in this episode.
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The set for the hotel is the same as in... 
...Episode #51 "The Unkind Philantropist" but there the hotel was located in Puerto Rico. (0:00)
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English Actor Peter Elliott was given an Asian look through an epicanthic fold via make-up - the result is not very convincing though. (0:06)
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The cars first drive through the backlot from right to left (notice the passage on the right) and then from left to right, this time filmed from that passage. (0:21)
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You can see the crew filming the scene mirrored in the car. (0:27)
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The name Judith Northwade presented by Seargent Leduc in the list as one of the names used by Jeannine Roger in the past was the name of Julie Christie's role in Episode #15 "Judith". Was it planned that Judith in the earlier episode is the same role as the one played by Sylvia Syms here? (0:42) [Submitted by Wojciech Trojanowski]