Today is the day, folks. Today is the day Castle comes to an end. After spending weeks wondering if the show was going to continue without its core romance between Castle (Nathan Fillion) and Beckett (Stana Katic), we won't have to bear witness to a Beckett-less Season 9, following the show's cancellation last week. Castle showrunners Terence Paul Winter and Alexi Hawley shot two endings in case the show was canceled, which means we will hopefully get to watch Caskett ride (or maybe walk — it is New York City) off into the sunset together, instead of worrying whether Beckett will die.

Before the series finale airs, there are a few mysteries that need solving first.

Castle: a farewell to Caskett

Who is LokSat?
It's the mystery that started the entire eighth season. Who is LokSat, the mystery man (or woman) in the CIA coming after Beckett? In the beginning, things pointed to Vikram as the likely culprit — and it still could be him. However, after spending so much time helping Beckett, could it really be Vikram? That "betrayal" would be too obvious and lazy. The series finale is expected to finally answer this question, but there's one that it doesn't look likely to answer...

What's the deal with Castle's missing time?
We now know Castle knew about LokSat, who sent him a message to stop looking into things should he ever recover his memories. But does that means we are going to finally learn all there is to know about his memories before the credits roll? Is LokSat the end of things? The last update we got on the memory front was that, at some point, Castle was in Los Angeles. Has he traveled anywhere else? We will have to wait and see, and while we do, there's one more thing we definitely need to know before things wrap up...

What will become of Parish?
This one seems the least likely of the three to get answered, but still, we learned a few weeks ago that Tamala Jones would be exiting the show along with Katic had it been renewed for a ninth season. So, what would have become of Lanie? Will she quit and move away? Will she finally find a relationship to commit to? Her dating life certainly became a fun B-plot the last few weeks. There were so many possibilities!

Castle's series finale airs Mondays at 10/9c on ABC.