In episode 6 of 'Stuart Fails to Save the Universe', Raj and his friends are faced with an existential threat that could destroy entire galaxies.

A romantic scene between Stuart (Kunal Nayyar) and Denise (Laura Spencer) provides a glimpse into their relationship as they contemplate their future together, chewing their cud in the process. For related coverage, explore our detailed analysis on Technology and Digital Systems.

Stuart and Denise's Intimate Moment

'Yeah, I think that could definitely be at the top of the list — to vomit more clearly or for longer into your mouth,' says Lauren Lapkus about her acting experience with cow-themed scenes.

Brian Posehn reveals that filming Kripke's sequences involved extensive wire work, which took a toll on his co-star John Ross Bowie.

'I was thrown around like a f**king ragdoll, Ryan!' says Bowie, who was dropped 23 feet during the sequence.

Kripke's Airborne Punishment

A projection of Stuart from a collapsing adjacent universe reappears and confirms that due to his quantum entanglement, 'you are the only one who can save the universe.'

'I'm not a hero,' says Stuart. 'I'm a broke ass, failed artist who owns a comic book store.'

Read More: What To Watch In September: A Printable TV Calendar Highlighting Every Major

Denise reminds Stuart that being a hero is a choice, and they decide to keep trying to save the universe.

Ultimately, their actions inadvertently save Kripke and Bert from their free fall, but they soon discover that everyone can read each other's minds in this new reality.

The foursome lands safely in yet another seemingly normal universe...

until they discover that everyone can read each other's minds.

"Stuart Fails to Save the Universe" Episode 6 marks the second appearance Kunal Nayyar's Raj might've been killed off in the post-apocalyptic universe , but the "Big Bang Theory" character is very much alive in this one, warning that entire galaxies are already disappearing — and that it may only be hundreds — not millions, not thousands, but just hundreds — of years before the entire universe ceases to exist.

But other than that, everything seems pretty much back to normal in this episode... except for the fact that humans descended from cows. That includes Stuart and Denise, who spend one of the episode's more intimate scenes lying in bed, contemplating their future together...

while chewing their cuds.