Basically everything I want in a series. Michelle Williams, Sam Rockwell, faultless acting, innovative use of timeline and structure, complexity of the story mirroring the complexity of our characters and their relationships, artistic editing choices. More importantly, using the obvious context (the musicals everyone knows) only to enhance the character-driven narrative, not to act as a crutch or become the obvious focus. The series never loses focus and that's a triumph.
I finished this series on Michelle Williams birthday, which was so extra.