The arch-villain in season 1 is named Murdoch Foyle. Two of the cleverest detectives on TV are William Murdoch of Murdoch Mysteries (2008) and Christopher Foyle of Foyle's War (2002).
Essentially, "King Memses' Curse" is part two of a story begun in "Murder in the Dark."
When Dot holds Hugh at gunpoint, the calendar on the wall reveals the date as Monday, December 19th. If the series takes place in the 1920s, that would make the year either 1921 or 1927. (The next December 19th on a Monday would occur in 1932. Furthermore, the calendar in "Death by Miss Adventure" indicated the year as either 1920 or 1926.)