The end is near for The Big Bang Theory. A new promo video released for the hit sitcom reveals that there's only ten episodes left to go, while Kaley Cuoco's Penny tries to seduce her husband, Leonard (Johnny Galecki). It's hard to believe that the series has been going strong for 12 seasons, but it's even harder to believe that they're pulling the plug after so much success. When it comes down to it, the cast needs a break, and now seems like a good time to stop everything and go on with new projects.

The upcoming episode of The Big Bang Theory is titled The Donation Oscillation and it revolves around Leonard donating his sperm to help Zack (Brian Thomas Smith) and Marissa (Lindsey Kraft). However, Penny has other ideas and tries to seduce Leonard into having sex with her before the big day, which makes Leonard go sleep on Sheldon (Jim Parsons) and Amy's (Mayim Bialik) couch. It's unclear why Penny insists on being intimate at that specific time, but we'll all learn soon enough.

While fans are bummed to see The Big Bang Theory go, the cast seems ready for the next chapter in their lives. Jim Parsons recently admitted that he did not want to do Season 13. And before Season 12 was even announced, Johnny Galecki hinted that this season would be the last. The actor said that it would be nice for the cast to spend time with their families since taping the show takes up so much of their lives. Even though they wanted the show to end, it doesn't mean that they aren't emotional about it coming to a close.

Related: Big Bang Theory Brings in William Shatner for Dungeons and Dragons Episode

Jim Parsons says that he hasn't shed a tear yet, but he thinks that when he does, he won't be able to stop. Kaley Cuoco revealed that she cries just thinking about the end, which has made the crew feel better and made them all comfortable about being open with their feelings. There's been a lot of ups and downs with The Big Bang Theory storylines over the last 12 seasons, but fans still keep coming back for more and some will more than likely shed tears like Cuoco when everything comes to a close.

It's unclear where the rest of The Big Bang Theory Season 12 will take us, but we do know that William Shatner will be making an appearance during an "epic" Dungeons and Dragons episode. He'll star alongside the cast and fellow guests including NBA legend Kareem Abdul Jabar, director Kevin Smith and Wil Wheaton. Also starring is real-life D&D player, Joe Manganiello. That's a pretty random reveal, but solid crew for the hit series and it's going to be funny to see them all interact together. You can watch the new promo teasing the end below, thanks to the Big Bang Theory YouTube channel.

Kevin Burwick