9. The Day The Eiffel Tower Went Berserk
If you've ever read the original Umbrella Academy comic books, then you'll surely remember the juvenile teams very first adventure, which took place on the street of Paris. In the story, the heroes assemble to investigate a number of mysterious deaths that seem to have all occurred when the Eiffel Tower threw them to their deaths.
Yes, you read that right, The Eiffel Tower kills people. In the story 'The Day The Eiffel Tower Went Berserk', the aforementioned monument is actually an alien space craft, and the secret lair of none other than a zombie-robot version of the towers real-life creator Gustav Eiffel.
During the episode "We Only See Each Other at Weddings and Funerals", as Klaus searches for items to pawn, his sister Allison instead chooses to search her late father's office for clues to help her understand what happened to him before his death.
At the exact moment she realises Klaus is hidden away under a desk, we catch a glimpse of a framed picture in the background. The image is of a newspaper clipping, depicting the Eiffel Tower, a definite throwback to this old school adventure.