The color grading slowly progresses from cold to warm along with Felicia's transformation into 1924 Cassandra. This is also reflected in the score, which introduces more and more jazz elements.
In the scene with Nicke at the antique shop, the mother and daughter are the actual owners of the shop and are playing themselves.
The door code Felicia enters in the first scene to get into her apartment building is "1924", the year Cassandra moved to Stockholm and received the necklace.
In addition to the main locations, many famous Stockholm landmarks from the 1920s make a cameo appearance, such as the City Hall (1923), Concert Hall (1926) and King's Towers (1924).