EXCLUSIVE: 'Supernatural' Star Misha Collins Teases 'Emotional Whiplash' in Season 10 Finale!

The CW

"There's some good and there's some terrible coming down the pipe."

It's the moment we've all been waiting for...

After 212 episodes of waiting, two of our most beloved Supernatural characters -- Castiel (Misha Collins) and Charlie (Felicia Day) -- are finally going to meet. (Someone break out the pie because we seriously need to celebrate!)

To help get you prepared for tonight's momentous occasion, we called up star Misha Collins and he spilled everything you need to know about their "happy meeting," Cas' fatal quest to recover his grace, and the "emotional whiplash" headed our way in the finale.

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Fans are thrilled that Castiel and Charlie are finally going to come face-to-face. What can you tease about their highly anticipated first encounter?
MC: Your excitement is reflected in the characters' excitement. Charlie, particularly, is bubbly and effusive when they are introduced to one another. It's definitely a happy meeting. I don’t know how we've been kept apart for so long, but it's like we've been friends for a long time at the outset.

Castiel is about to embark on a very important road trip with an unlikely partner – Metatron. Why do you want fans to know before tuning in to Wednesday's episode?
Well if Cas doesn’t get his grace back, he is going to die. So he is sort of out a limb here not necessarily trusting Metatron, but having to take him at his word because he has nothing else to go on for recovering his grace. So he is having to let Metatron lead him to his grace -- or what he says is his grace -- and yet the entire time he's unsure whether he'd being led into a trap, or whether he's being lied to completely. We've always seen Metatron operating with hidden intentions and this is going to be another one of those situations. It will not end happily with Cas getting his grace back and then sending Metatron back to jail—I'll spoil that for you.

Supernatural is not afraid to kill off fan favorite characters. Do you think viewers should be seriously worried about Cas' fate?
Yeah it's always something to take seriously. I think that's something that gives the show in general so much more of an emotional impact when you're watching it. If you're watching a show and you just know that there's no way that any of the characters that you like are going to die, it really kind of lowers the stakes. But in Supernatural, there have been a lot of character over the years that the fans have really liked that have been killed -- including Sam and Dean's kind of father figure Bobby who was on the show for six or seven years and was killed. We've seen him in dream sequences and heaven sequences but for all intents and purposes, the character is not on the show in any kind of regular basis anymore. That sort of thing gives a lot of teeth to the threat of the characters' mortality in any given moment. Fans in general take these things seriously for good reason.

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If – fingers tightly crossed – Cas recovers his grace, could we possibly see him with a new love interest?
Oh good question! Although I have to say that's not something that we're going to be getting into. The end of this season is definitely not heavy on the romance, it's more like we're trying to save our friend and possibly head off some really horrible things that are going to ruin the world. So yeah there's not a lot of [romance] going on? Cas is an angel, it's complicated, who knows?

What is the one thing you want fans to know as we approach the end of Supernatural's tenth season?
Well we're inching up on the finale here and this is, in typical Supernatural fashion, fans are going to experience emotional whiplash of 'Oh thank God' to "Oh sh-t!' in the last two beats of the season. So there's some good and there's some terrible coming down the pipe.

Lastly, you're prepping his annual charity scavenger hunt – GISHWHES – for fans who still don't know about this amazing event, what should they know and how can they get involved?
Well it was something started on kind of on a lark five years ago and it's GISHWHES, which stands for "Greatest International Scavenger Hunt the World Has Ever Seen" -- and I know it flows trippingly off the tongue [Laughs] And it is exactly what its name suggests. It is the Guinness World Record holding largest scavenger hunt in the world and thousands and thousands of people participate all over the world and it is so much fun. So if you sign up online on our website then we will put you on a team with people that you will communicate with virtually and then compete in the scavenger hunt. The winning team this year will be brought on an all-expenses-paid trip with me to Costa Rica. Just awesome trips for the winners and we also raise lots of money through the scavenger hunt for Random Acts, which is a non-profit that I started and we just finished building a school/orphanage/community center in Haiti. So we're doing some really cool projects that I'm proud of with the money and the scavenger hunt itself is super super fun.

Supernatural airs Wednesdays at 9 p.m. on The CW.