Why does Sheldon Cooper feel the need to knock on the door three times before entering a room? Is there a reason behind it? Let’s find out!
For almost ten years, two socially awkward physicists, Sheldon Cooper and Leonard Hofstadter entertained us with their geekiness on ‘The Big Bang Theory’. During the 12 seasons, we saw many eccentric personalities. But no one matched the quirkiness of Sheldon Copper. One of his most quirky traits was his obsessive need to knock on the door in a particular order. One of our favourite sights on the show was definitely Sheldon knocking on the door of his friend and neighbour, Penny. But, given Sheldon’s numerous quirks, the knock must have had a reason behind it, right? Was it because of his need to be in control of his environment? Let’s find out more about everyone’s favourite Sheldon Cooper and his knocking habit.
HIGHLIGHTS —
- Beginning of the knock
- The real reason behind Sheldon’s knocking
- Kaley Cuoco recreates the “Penny knocks back at Sheldon” episode
Sheldon’s habitual knock consists of three knocks that are repeated three times for a total of nine knocks. After every three knocks, he would state the person’s name and then enter a space. His knock has mostly been experienced by his next-door neighbour, Penny. Sheldon’s knocking on the door habit has been described by Amy as an obsessive-compulsive disorder. Though Sheldon never agreed to it.
Beginning of the knock
The first time Sheldon ever knocked on anyone’s door was in the second episode (“The Big Bran Hypothesis”) of the first season of ‘The Big Bang Theory‘. However, it failed to get noticed as the show was just finding itself in its initial episodes. Before Sheldon’s knocking became a part of his quirky personality, it went through several changes. It was in the episode “The Loobenfeld Decay“, where Sheldon’s iconic knock was featured for the first time. He knocked three times on Penny and Leonard’s door.
Sheldon’s persistent knock was officially caught on “The Euclid Alternative” episode. It soon became a part of his personality with a few variations here and there, throughout season 1 and 2.
In “The Habitation Configuration” episode, when Sheldon is drunk, he knocks on Wil Wheaton’s door two times instead of three. He later realized and corrected himself by knocking again in the middle of his conversation with Wheaton.
The real reason behind Sheldon’s knocking
Sheldon’s habitual knock consists of three knocks that are repeated three times for a total of nine knocks. After every three knocks, he would state the person’s name and then enter a space. His knock has mostly been experienced by his next-door neighbour, Penny. Sheldon’s “knocking on the door” habit has been described by Amy has as an obsessive-compulsive disorder. Though Sheldon never agreed to it.
In season 10’s “The Hot Tub Contamination” episode, Sheldon finally revealed the real reason behind his compulsive habit. While eating ice-cream with Penny, he told her the knocking was due to a childhood incident. It is also the reason why Sheldon found it extremely difficult to be physically intimate with his girlfriend, Amy.
Sheldon explained to Penny that the incident happened when he was thirteen. One day he came home early for spring break from college because they ran out of math to teach him. His mother was at Bible study. So, he expected the house to be empty. Sheldon walked into the house and heard some noises that were coming from his parent’s bedroom. He quickly went ahead and opened the door. There he saw his father having sex with another woman. Since that traumatic incident, Sheldon never opened a door without knocking three times on the door. He further explained how the first knock was traditional. The second and third knock was for people to get their pants on. He also confessed how he never told anyone about his father’s affair.
In Season 10’s “The Hot Tub Contamination” episode, Sheldon finally revealed the real reason behind his compulsive habit. While eating ice-cream with Penny, he told her the knocking was due to a childhood incident. It is also the reason why Sheldon found it extremely difficult to be physically intimate with his girlfriend, Amy.
Kaley Cuoco recreates the “Penny knocks back at Sheldon” episode
Kaley Cuoco recently made her debut video on a Tiktok. She is famously known for playing the role of Penny on ‘The Big Bang Theory’. In the TikTok video, Cuoco reprised her role as Penny alongside internet star Pierson Fode. Together they recreated the Penny knocks back at Sheldon episode. In the video, we can see Fode playing the role of Sheldon knocking the door persistently and lip-syncing to his voice. The video ends with Cuoco opening the door. Fode shared the video on his Instagram too and captioned it “Penny actually opened the door #bigbangtheory #penny #sheldon @kaleycoocoo – go follow her it’s her first TikTok”. To which Cuoco replied: “I feel like I’ve now made it.” She also shared the video as a story on her Instagram page.
