This is a masterful spin on the Sliding Doors/Butterfly Effect idea that seemingly tiny events can have life altering ripple effects. All the actors excelled in their dual roles and seeing different versions of each character in the parallel worlds gave me a lot to chew on. This show admirably wrestles with deep questions. What makes us who we are? How much control do we have over our own fates? How do we derive meaning in life? The mystery was perfectly structured: intricate enough to keep me hooked but never too convoluted. The villains had fascinating motivations and goals and were appropriately depraved. It's not a traditional romance but the love the leads had for each other was beautifully conveyed. Just a stellar production in every way.