Robert "Robby" Keene is one of the main protagonists of Cobra Kai. He is one of the main protagonists of Season 1 and Season 2 and an anti-hero in Season 3 and Season 4.
He is the son of karate sensei Johnny Lawrence and Shannon Keene.
Initially a troublemaker that breaks the rules, Robby begins to change his ways after working with Daniel LaRusso. He becomes the first disciple of the new generation of Miyagi-Do Karate, and becomes one of the best.
Unfortunately, a fight with his rival Miguel Diaz, in which he severely and gravely injures him by accident, gives him a short sentence in juvie. Following his release from juvie however, Robby is left conflicted over where his alliances lay, leaving him susceptible to the smooth-talking John Kreese. Through corruption from Kreese, Robby is recruited into the new Cobra Kai Dojo, to take seek revenge against his father and Miguel.
He is portrayed by Tanner Buchanan
Robby is Johnny's estranged son from a failed relationship with Shannon Keene.
Johnny was absent for much of Robby's childhood which made Robby to resent him deeply and causes a strained relationship between the two. With his mother frequently behind bars and his father absent since his birth, Robby has no role models in his life. Robby falls in with drugs, stealing, and dropping out of school.
Robby drops out of school when he gets in trouble for drugs, after which he and his friends Cruz and Trey spend their days engaged in petty theft as seen when they are stealing laptops from Tech Town. Johnny tries to reconcile with him at the apartment he lives at with his single mother, but he rebuffs him.
To spite his father for neglecting him in favor of Miguel, Robby begins working at LaRusso Auto Group. Despite his original ulterior motive, Robby grows to appreciate Daniel's faith in him and turns against Cruz and Trey when they try to rob the dealership. Robby becomes Daniel's Miyagi-Do karate student and flourishes under this tutelage. However, when Daniel finds out that Johnny and Robby are father and son after Johnny shoves Daniel and breaks one of his All-Valley trophies, Daniel furiously banishes Robby from his home and business as punishment for his deception.
Undaunted by this rejection, Robby enters the All-Valley tournament with no affiliation and advances towards the finals, impressing Daniel. This, combined with Amanda's encouragement to forgive Robby and Robby's apology for hiding the fact that he is Johnny's son, convinces Daniel to reconcile with Robby, officially become Robby's sensei again and allow Robby to fight under the Miyagi-Do name during the final match against Miguel. Robby sustains a shoulder injury from Hawk's illegal attack during the semi-finals and ultimately finishes second to Miguel, who exploits Robby's shoulder injury to win a close match. Impressed with Robby's performance and disgusted with his students' increasingly thuggish behavior, Johnny apologizes to Robby, who politely accepts it, implying that Robby still cares about Johnny somewhat despite their strained relationship. Regardless of this loss, Daniel praises Robby's performance and takes him to Mr. Miyagi's old rest house to explain his plans to restart the Miyagi-Do dojo with Robby as his senior protege.
Robby moves in with the LaRussos after his mother Shannon abandons him and leaves with her boyfriend Rick to go on vacation to Mexico, and is evicted from their apartment due to unpaid bills. He and Sam bond closely while training and enter a short relationship, however the relationship is short-lived as she cheats on him with Miguel while they are attending Moon's party due to Sam finding out from Aisha that Miguel returned Miyagi's Medal of Honor to Robby, which had been stolen by Hawk. After Robby takes Sam to Johnny's apartment after getting drunk at a party, Daniel accuses Robby of following the footsteps of his father and cuts ties with Johnny and Robby.
With his mother in rehab and his relationship with Daniel tarnished, Robby is forced to live with Johnny, and the pair slowly start to reconcile. During the karate war between the Cobra Kai and Miyagi-Do students at school, Robby once again gets into a fight with Miguel, who taunts him by mocking his relationship problems with Johnny and Sam.
After a lengthy fight, Miguel eventually traps Robby in an arm lock and nearly decides to break his arm to end the school brawl once and for all, but decides to let go of him after remembering Johnny's advice of showing mercy. However, Robby, furious with Miguel for taunting him about his relationship problems with Johnny and Sam and taking advantage of Sam at Moon's party, furiously retaliates by kicking Miguel over the balcony railing, accidentally sending him falling off the second floor and crashing spine-first on a stair handrail, paralyzing him and rendering him unconscious. Shocked and horrified at the fact that he accidentally crippled Miguel, Robby flees the scene while Sam, Hawk and a police officer check on an unconscious Miguel.
Robby is subsequently expelled from West Valley High School for crippling Miguel, and goes into hiding as a wanted fugitive for several weeks, stealing a used Dodge Grand Caravan from the LaRusso dealership and living out of a homeless camp. After chasing down several leads, Daniel discovers that a devastated Robby is visiting his mother Shannon in rehab to seek comfort and support and arranges to have the police arrest him, believing that Robby will get a lighter sentence if he surrenders. However, as the police arrive and interrupt Daniel while he is trying to convince Robby to agree to the plan for a lighter sentence, Robby angrily accuses Daniel of betraying him and ends their friendship by coldly ordering Daniel not to visit him in juvenile hall.
During his incarceration at Sylmar Juvenile Detention Center, Robby feels abandoned when Johnny misses a scheduled visit to provide moral support to Miguel's family during his surgery and subsequently cuts ties with Johnny. Kreese takes advantage of Johnny's neglect to visit Robby, and upon finding out that Robby is being bullied by a group of inmates, suggests that he adapt to the Cobra Kai mentality of striking first. Taking Kreese's lessons to heart, Robby gains the upper hand on the bullies, winning their respect. Around mid-December, Robby is released from juvie, but rebuffs both Daniel and Johnny when they arrive to pick him up due to his resentment towards them. After discovering Sam and Miguel are together again at the Miyagi-Do dojo, Robby furiously accuses Sam of dumping him for Miguel after he was sentenced to juvenile hall. With nowhere else to go, Robby furiously ends his relationship with Samantha and goes to Cobra Kai, where Kreese agrees to take him in. Robby is initially reluctant to join Cobra Kai due to Hawk's resentment towards him for his actions against Miguel at the end of the school brawl but Tory convinces him to stay with Cobra Kai, the two soon befriend each other and find common ground in each other's broken home lives as well as their own betrayals from Johnny, Sam and Miguel. As the newest member of Cobra Kai, Robby proves himself to Kreese and the rest of the Cobra Kai students (except for Hawk) after stealing a snake from the zoo.
While Tory leads the Cobra Kais that night in an attack on the LaRusso house, Kreese keeps Robby behind at the dojo to train him. When Johnny shows up at the dojo to confront Kreese over the attack on Miguel, he is horrified to see Robby wearing a Cobra Kai gi. Robby offers Johnny to re-join Kreese in Cobra Kai, but Johnny rejects, and attacks Kreese. Robby steps in and defends Kreese and engages in a fight against Johnny after angrily dwelling on the past about how Johnny was never there for Robby we he needed him. Robby is then unintentionally knocked out by Johnny who reluctantly pushes him into a set of lockers after trying to reason with him to no avail. Daniel joins the fray, and he and Johnny defeat Kreese before Miguel and Sam intervene to talk them out of killing him. When Robby regains consciousness, he coldly orders Daniel, Johnny, Miguel, and Sam to leave before continuing his training with Kreese.
Robby aids Kreese and Terry Silver with leading the Cobra Kais, training them in Miyagi-Do techniques so that they can better counter Miyagi-Do and Eagle Fang. He also befriends a young student named Kenny Payne whom he mentors due to him struggling to fit in at school and dealing with bullies including Daniel's son Anthony, as well as Johnny’s students Hawk and Bert. Robby confronts Johnny about the bullying and tells him if the bullying doesn’t stop, he will be forced to put an end to it himself.
In the finals at The All Valley, after Miguel chooses not to return, Robby faces off against Hawk who has returned to using his original name Eli and is allied with Miyagi-Do. As they both know the Cobra Kai and Miyagi-Do techniques, Robby and Eli fight to a draw, leading to a sudden death overtime for the first time since the 1985 All-Valley Tournament (from The Karate Kid Part III) and earning him Eli's respect. Ultimately, Eli defeats Robby and becomes the All-Boys champion after hesitating to finish him off when Kenny cheers for him from the sidelines. Despite losing, Cobra Kai still becomes grand champion when Tory Nichols defeats Samantha LaRusso at the girls finals. Later, at the now-abandoned Cobra Kai dojo, Robby breaks down and admits he's tired of blaming Johnny for his problems and reconciles with him, having become disturbed at witnessing Kenny's increasingly vengeful actions and violent behavior towards Daniel’s son Anthony before his match with Eli as a result of Silver and Kreese's teachings, which made Robby realize what his anger had turned him into and how he failed to prevent Kenny from going down the same path.