8.7/104,918 votes#1 - The Robotic Manipulation
Season 4 Episode 1 - Aired 9/23/2010
Penny tags along on Sheldon's first ever date; Wolowitz finds a new use for a robotic arm.
Director: Mark Cendrowski
Writer: N/A
8.3/104,404 votes#2 - The Cruciferous Vegetable Amplification
Season 4 Episode 2 - Aired 9/30/2010
Realizing he will not live long enough to download his consciousness into a robot body, Sheldon tries to extend his life span.
Director: Mark Cendrowski
Writer: N/A
7.9/104,162 votes#3 - The Zazzy Substitution
Season 4 Episode 3 - Aired 10/7/2010
The guys are concerned as Sheldon searches for an alternative to human companionship.
Director: Mark Cendrowski
Writer: N/A
8.0/104,140 votes#4 - The Hot Troll Deviation
Season 4 Episode 4 - Aired 10/14/2010
An embarrassing secret of Wolowitz's comes to light, while Sheldon and Raj have a small war at work.
Director: Mark Cendrowski
Writer: N/A
7.6/103,978 votes#5 - The Desperation Emanation
Season 4 Episode 5 - Aired 10/21/2010
Leonard realizes he’s the only one without a girlfriend, while Sheldon wants to get rid of his.
Director: Mark Cendrowski
Writer: N/A
8.0/104,053 votes#6 - The Irish Pub Formulation
Season 4 Episode 6 - Aired 10/28/2010
Leonard keeps an affair a secret from Sheldon, Howard and Raj.
Director: Mark Cendrowski
Writer: N/A
8.0/104,078 votes#7 - The Apology Insufficiency
Season 4 Episode 7 - Aired 11/4/2010
Sheldon's answers during an FBI interview put Wolowitz's security clearance in jeopardy.
Director: Mark Cendrowski
Writer: N/A
8.1/104,087 votes#8 - The 21-Second Excitation
Season 4 Episode 8 - Aired 11/11/2010
While the guys camp in line for a long-awaited movie screening, Penny and Bernadette invite Amy to her first slumber party.
Director: Mark Cendrowski
Writer: N/A
8.4/104,274 votes#9 - The Boyfriend Complexity
Season 4 Episode 9 - Aired 11/18/2010
Penny asks Leonard to lie to her father, while Howard, Raj and Bernadette pull an all-nighter at a telescope.
Director: Mark Cendrowski
Writer: N/A
7.6/103,958 votes#10 - The Alien Parasite Hypothesis
Season 4 Episode 10 - Aired 12/9/2010
Amy finds she has sexual feelings for Penny's ex, while Koothrappali and Wolowitz try to prove who would be the better superhero.
Director: Mark Cendrowski
Writer: N/A
8.6/104,546 votes#11 - The Justice League Recombination
Season 4 Episode 11 - Aired 12/16/2010
The guys find a "super" use for Penny's new boyfriend, Zack, when they enter a costume contest as the Justice League.
Director: Mark Cendrowski
Writer: N/A
7.5/103,951 votes#12 - The Bus Pants Utilization
Season 4 Episode 12 - Aired 1/6/2011
Leonard's idea for a smartphone app derails his friendship with Sheldon.
Director: Mark Cendrowski
Writer: N/A
8.2/104,250 votes#13 - The Love Car Displacement
Season 4 Episode 13 - Aired 1/20/2011
Bernadette runs into her ex-boyfriend while attending a science event with Wolowitz.
Director: Anthony Joseph Rich
Writer: N/A
7.7/104,016 votes#14 - The Thespian Catalyst
Season 4 Episode 14 - Aired 2/3/2011
Hoping it will make him a better teacher, Sheldon has Penny give him acting lessons. Raj has fantasies about a friend's girlfriend.
Director: Mark Cendrowski
Writer: N/A
7.7/103,963 votes#15 - The Benefactor Factor
Season 4 Episode 15 - Aired 2/10/2011
A wealthy donor to the university makes Leonard consider how far he's willing to go for the sake of science.
Director: Mark Cendrowski
Writer: N/A
7.8/103,836 votes#16 - The Cohabitation Formulation
Season 4 Episode 16 - Aired 2/17/2011
As Wolowitz contemplates taking things with Bernadette to the next level, Leonard rekindles his relationship with Raj's sister.
Director: Mark Cendrowski
Writer: N/A
7.9/103,872 votes#17 - The Toast Derivation
Season 4 Episode 17 - Aired 2/24/2011
Sheldon becomes concerned when everybody begins to hang out at Raj's apartment and discovers Leonard is the center of the group.
Director: Mark Cendrowski
Writer: N/A
8.1/104,055 votes#18 - The Prestidigitation Approximation
Season 4 Episode 18 - Aired 3/10/2011
Sheldon is baffled by Wolowitz's magic trick. Meanwhile, Leonard realizes dating Priya may make it impossible to continue being friends with Penny.
Director: Mark Cendrowski
Writer: N/A
8.0/103,940 votes#19 - The Zarnecki Incursion
Season 4 Episode 19 - Aired 3/31/2011
Sheldon's online-game account is hacked by Todd Zarnecki, who then proceeds to steal all his items prompting the guys to go on a quest to retrieve them. Penny, Bernadette and Amy discuss how Penny groomed Leonard to be willing to try various things and more adventurous boyfriend... for some other woman — Priya.
Director: Peter Chakos
Writer: N/A
8.2/103,932 votes#20 - The Herb Garden Germination
Season 4 Episode 20 - Aired 4/7/2011
Sheldon and Amy decide to start several rumors about the others as a test. Meanwhile, Howard takes his relationship with Bernadette to even higher level.
Director: Mark Cendrowski
Writer: N/A
8.2/104,037 votes#21 - The Agreement Dissection
Season 4 Episode 21 - Aired 4/28/2011
When Leonard spends too much time in the shower with Priya, Sheldon charges Leonard with two violations of the roommate agreement. However, before he can get too far, Priya uses her skills as a lawyer to nullify the charges due to the agreement's vague wording, much to Sheldon's dismay. When the guys take advantage of Priya's skills in order to eat Greek food on pizza night, Sheldon goes to Penny, who invites him to a girls' night out with Amy and Bernadette, which Sheldon agrees to after Penny mentions that they may be talking trash about Priya. After the girls drink some cocktails, they decide to take Sheldon dancing, which Sheldon reluctantly goes along with. After dancing, Sheldon takes an intoxicated Amy back to her apartment and as well as talking about Priya, meets a monkey who is addicted to smoking cigarettes. Amy tells Sheldon not to give in to Priya's law skills, before kissing him and going to her bathroom to vomit.
Director: Mark Cendrowski
Writer: N/A
7.7/103,819 votes#22 - The Wildebeest Implementation
Season 4 Episode 22 - Aired 5/5/2011
Raj attempts to cure his social anxiety disorder while Penny uses Bernadette to spy on Leonard and his girlfriend.
Director: Mark Cendrowski
Writer: N/A
8.0/103,888 votes#23 - The Engagement Reaction
Season 4 Episode 23 - Aired 5/12/2011
When Howard finally breaks the news to his mom that he's engaged to Bernadette, it lands her in the hospital.
Director: Howard Murray
Writer: N/A
8.5/104,136 votes#24 - The Roommate Transmogrification
Season 4 Episode 24 - Aired 5/19/2011
When Bernadette receives her PhD, Wolowitz feels emasculated. Raj and Leonard swap places and Penny does something she's regrets.
Director: Mark Cendrowski
Writer: N/A
The Best Episodes of The Big Bang Theory Season 4
Every episode of The Big Bang Theory Season 4 ranked from best to worst. Discover the Best Episodes of The Big Bang Theory Season 4!
Physicists Leonard and Sheldon find their nerd-centric social circle with pals Howard and Raj expanding when aspiring actress Penny moves in next door.
Genre:Comedy
Network:CBS
Season 4 Ratings Summary
"The Robotic Manipulation" is the best rated episode of "The Big Bang Theory" season 4. It scored 8.7/10 based on 4918 votes. Directed by Mark Cendrowski and written by N/A, it aired on 9/23/2010. This episode is rated 0.4 points higher than the second-best, "The Cruciferous Vegetable Amplification".