Board Thread:Spoilers!/@comment-27060727-20170222030619/@comment-24674051-20170228214834

I"m going to be curious to see how this will lead into the Finale. What sort of plot is going to be set up. My instinct tells me that the Wedding will be integral to the Finale, since it will most likely reflect the Wedding that we got with the Pilot. And having the show come full circle in that regard would be an expected plot.

Which means that the musical is likely preparations for the wedding. The musical may not necessarily be a one-off, but I think the major plot points (Black Fairy and Gideon) will be resolved by 6x19, leaving primarily the wedding and maybe some minor plot points to resolve prior to the finale.