'The Big Bang Theory' season 9 episode 21 spoilers: The group watches 'Game of Thrones,' Howard gets rushed to the hospital

Following a weeklong hiatus, "The Big Bang Theory" season 9 returns this Thursday with a new episode. In "The Viewing Party Combustion," the gang will face another hiccup among their group, as Leonard (Johnny Galecki) and Sheldon (Jim Parsons) will have another one of their petty arguments.
As stated in the episode title, the group will have a "Game of Thrones" viewing party. What seems to be an innocent bonding time for them will eventually lead to an unexpected trouble, as the group will argue about their own opinions on the show. While Leonard , Howard (Simon Helberg), Amy (Mayim Bialik), Bernadette (Melissa Rauch) and Raj (Kunal Nayyar) discuss the HBO series, it will turn into a heated argument.
According to the show's spoiler website, Sheldon and Penny (Kaley Cuoco) will choose to stay out of the discussion. Halfway through the show they are watching, Leonard will hand out snacks for them to munch on. He unknowingly gives Howard a snack with peanuts in it, causing the latter to have a terrible allergic reaction. Howard is then rushed to the hospital in the middle of the episode.
As noted by The Futon Critic, the official synopsis for Episode 21 reads:
"The Viewing Party Combustion - Everyone must choose sides when a small argument between Leonard and Sheldon erupts into a heated fight during a group get-together, on The Big Bang Theory."
Furthermore, a synopsis for episode 22 titled "The Fermentation Bifurcation" has also been released, which reads:
"When Leonard, Penny, Amy, Howard, Raj and Claire all go out to a wine tasting party and they run into Zack who hits on Claire. Meanwhile, Bernadette and Sheldon spend the night at 4A where they play games and end up having a fun night."
The latest episode from "The Big Bang Theory" season 9 airs Thursday April 21, 8:00 p.m. EST on CBS.