Season 10, Episode 05 – “The Hot Tub Contamination”
Amy and Sheldon’s live-in relationship may be in the toilet after he accuses her of not following the bathroom schedule. Meanwhile, Howard and Bernadette’s secret stay-cation is interrupted by interfering interlopers who are sneaking into their hot tub.
What happens when hyperintelligent roommates Sheldon and Leonard meet Penny, a free-spirited beauty moving in next door, and realize they know next to nothing about life outside of the lab. Rounding out the crew are the smarmy Wolowitz, who thinks he’s as sexy as he is brainy, and Koothrappali, who suffers from an inability to speak in the presence of a woman.