He was voiced by Bumper Robinson.
Rook is tall, with periwinkle-blue colored fur, black markings on his face, and pointed ears. The middle of his face, his chest and his stomach are white. He has black stripes on his shoulders, waist, lower legs and lower arms. He carries the Proto-Tool on his shoulder and wears very durable blue-and-black Proto-Tech Armor.
Unlike Ben, Rook is more stoic and prefers to think before acting. He used to treat Ben more like a superior instead of a friend/partner as he usually addressed him as 'sir' when they first met. He now tends to see Ben as a lesser or equal being such as saying he always has to save Ben and that, "[Ben] wouldn't even be alive without Rook's help." Although, Ben still manages to impress him from time to time. While he is very intelligent, his lack of experience can make him somewhat naive and often the rear of Ben's constant jokes. He seems to dislike chili fries but he is crazy about meatball subs.
Rook still has difficulty understanding his Earth expressions, and he says that he still can hardly deal with 16 year old Ben. However, in Many Happy Returns, when Ben says that he doesn't always get Rook, but finds him to be cool, Rook explains that the feeling is mutual.
Rook is shown to be formal, such as initially calling Ben "sir" or referring to Gwen as "Miss Tennyson." When Rook first met Ben in The More Things Change: Part 1, he was respectful of him, and in The Frogs of War: Part 2, Kevin exasperatingly points out that he's "so polite." Rook never uses contractions except when he heard that his former teacher hurt his father.
Generally speaking, Rook is open-minded and gets along well with everyone, though there are certain individuals that push his patience to the limit, and he sometimes has to resist an urge to hit them, like Pax and Kundo. When his family is in danger, Rook is willing to defend them by any means necessary. He considers the Vreedle Brothers to be his sworn enemies, due to them destroying the Plumbers' Academy and with this, making him taking his final exams on an asteroid. However, when he met Sceles Vreedle, he was very confused for multiple reasons. He was attracted to her, but had mixed feelings due to the fact he already has a girlfriend who is, in his opinion "quite attractive". Plus the fact that she was a vreedle and a criminal; his sworn enemy who he as a textbook plumber was supposed to be opposed against.
Rook made his debut in The More Things Change: Part 1, when he is called to Earth by Max Tennyson to be the partner of his grandson, Ben Tennyson. Rook first meets Ben in Mr. Baumann's shop, where he is quietly enjoying his meal in disguise. Ben, in the form of Cannonbolt sits next to him and asks Rook if he can have his food. Just as Cannonbolt is about to begin eating, the trio of alien criminals arrive. Cannonbolt starts to fight the criminals, causing major havoc. While everyone is escaping, Rook continues his meal calmly. After the criminals planted a bomb in the store and Ben is unable to transform, Mr. Baumann sarcastically mentions that Ben's friends should show up and save the day. Hearing that, Rook drops his food and starts to run towards the criminals. He quickly takes down the villains, then introduces himself to Ben and reveals that they are partners now. Rook tells Ben that it is an honor to meet him and that he had learned about his heroics at the Plumbers' Academy. Ben transforms into Bloxx and tells Rook to disarm the bomb, while he takes down the criminals. Rook tells that he can't disarm the bomb in time and blows a hole on the wall of Mr. Baumann's shop in order to detonate it away from the populous. They managed to move the bomb so it was able to explode further away. However, the criminals escaped by running into the crater that the explosion caused where Ben, Rook and Khyber's dog follows them.
In The More Things Change: Part 2, Ben and Rook continue to chase the criminals in a newly discovered Undertown. Rook begins to chase Fistina who manages to run into a tunnel along with Bubble Helmet. However, Liam gets left behind and Rook is able to shoot an electric web at him with his Proto-Tool. Rook and NRG start to question Liam but a hover bus is knocks them over and takes them to the Undertown market. Rook wants to chase the lowlifes but Ben tells him that they should rather be exploring. Ben is trying to enjoy Undertown, however, Rook constantly begins to interrogate and scare away citizens. Ben tells him to relax and that the bad guys will eventually come to them. Suddenly, Buglizard appears and start to fight Ben who accidentally turns into Water Hazard. Rook wants to help him but Ben tells that he got this. However, Buglizard quickly takes down Water Hazard without taking one hit, he then tells Rook that it is time for him to interfere. Rook shoots an energy rope at Buglizard which wraps her mouth for a short time and makes Water Hazard overpower her. Khyber, seeing that two fight against one, calls the situation unsporting and whistles retreat to his pet. Rook tells Ben that he had found out the location of Bubble Helmet and leads him to the Gas House. Rook kicks the door and tells everyone to put their appendages to the air. Ben, turning into Terraspin tells him that he shouldn't always reveal his badge and absorbs the poisonous gas to make the customers choke.
They find Bubble Helmet and ask who is behind the shakedowns. Bubble Helmet says that he will tell them as soon as he can breathe again and Rook, not knowing the common trick puts his helmet back onto his suit. While, following an escaped Bubble Helmet, Terraspin realizes how unexperienced Rook is and that he hasn't fought any actual bad guys so far. It turned out that Bubble Helmet lead them straight to his boss, Psyphon. They begin to fight with Psyphon's henchmen as well as start to destroy his shakedown machines. Psyphon manages to take down Ben and is about to torture him when Buglizard appears again. Psyphon retreats and Rook follows him, while Shocksquatch fights Buglizard. Rook gives a final warning to Psyphon who starts to shoot laser beams at him. Psyphon becomes amazed after seeing Rook's armor and that his attacks made no damage on it.
Rook tells him that the armor is not for sale, not knowing Psyphon didn't mean to buy it. Meanwhile, the fight between Shocksquatch and Buglizard caused a tunnel to collapse right onto Psyphon. At the end of the episode, after everyone got arrested Rook brings Chili Fries to Ben which makes him finally accept Rook as his new partner.
In A Jolt from the Past, Rook and Max were kept waiting at the Plumber HQ by Ben who was late because he dropped by Mr. Smoothys. Rook tells Ben that instead of his car, they will use Rook's Proto-TRUK from then on. Ben's first impressions of the vehicle were negative but after Rook transformed it into its space ship mode Ben admitted that sometimes he can be kind of awesome (with the emphasis on sometimes), much to Rook's joy. After they left the base, Rook felt like Ben was angry with him. Ben tells him that he is just bored and he hasn't been acting like a superhero lately, then he apologizes to Rook for keeping him waiting around. Rook tells Ben that he is looking forward to their partnership, after mentioning how many times he saved the universe and that he hopes that Ben will live up to the legends. Rook mentions that he thinks Alien X is a just rumor made up by a fan but Ben tells him that Alien X is real. Rook gets excited and asks Ben to turn into Alien X immediately but due to former incidents, Ben opposes. Ben then tells Rook to find him some hero-ing to do and he will then live up to the legends. Unfortunately, Ben constantly fails to show off his abilities, since aliens in Bellwood act natural opposing what he was previously experiencing. After a lunch break, they spot a guy who is using alien technology and begin to follow him.
However, the guy shoots at them and escapes with a muscle car, so they begin to chase him. After a quick chase, they capture the guy and quickly discover that he uses Nosedeenians to power his car. Rook tries to fight the Nosedeenians but due to lack of experience with them, he quickly gets tricked and zapped continuously. Ben and Rook split up, so Rook can tell Ben where the aliens are heading. While chasing them as Clockwork, Ben realizes that the aliens are not escaping but leading them to an old storage. They enter the building where they discover that someone is using the Nosedeenians as a power source. They soon get trapped in an electric field, however Rook quickly sets them free.
He, with the help of Bloxx, defeats and captures the thugs while their leader manages to get into a robot suit. Rook starts to shoot at the armor but Ben explains him that they can't fight back due to the Nosedeenians. With the help of Ben's new transformation, they manage to beat Fistrick and save the Nosedeenians. After the bad guys got taken away by the Plumbers, Rook says that the Tennyson legends always end with some type of beverage, however Ben corrects him that at night they eat chili fries, much to Rook's disappointment.
Powers and Abilities
Rook is a highly skilled combatant, both from his Plumber training and the tutelage of his Revonnah Kai teacher, Kundo. In addition to being Kundo's top student, Rook has since supplemented this fighting style with other techniques and tactics from his various missions as a Plumber, ultimately being able to best his teacher in fair combat.
Rook can jump several stories high. Rook has also been shown to be very nimble and has impressive acrobatic skills.
Rook is a master in terms of strategy and battle tactics. He also provides an amount of common sense to offset Ben's impulsiveness and lack of subtlety. Rook's encyclopedic knowledge of certain Earth trivia has proven to be useful at times. He also can understand Sotoraggian language. Rook shows very impressive soccer skills, having learned the game at the Plumber Academy.
Rook has advanced knowledge of magic. However, it required him to be in close proximity of the Alpha Rune to actually perform magic himself as he still had a slight bit of trouble pronouncing the words to cast spells from Gwen's Spellbook.
Rook is quite proficient in the usage of technology and machinery having shown a remarkable skill for creating electronic jamming devices when he fashioned an electron entanglement disruptor to escape an electromagnetic barrier. This skill further showcases itself when he is working around the functions of either his Proto-Tool or refitting and engineering his Proto-Truk, given his notice of his younger brother's modifications to a harvester for space flight showcases his keen eye for mechanisms. Such is Rook's mechanical genius that even fellow automotive enthusiast and gearhead Kevin Levin would call upon the former's unique expertise in augmenting his own ride to make it physically impervious to destruction.
Rook uses the Proto-Tool to help him in battle. He is adapted to using the Proto-Tool as a sword, bow, grappling hook, blaster, and various other things.
Rook has been shown to be an incredible marksman with the Proto-Tool many times. He was able to shoot Fistrick's tank from far away on a crane.
Rook wears Proto-Tech Armor, which is strong enough to protect Rook from a major explosive shock wave. The only thing shown to be able to damage the armor was Kundo's "stone-cutter" technique.
Rook used the Proto-TRUK as his primary vehicle until it was destroyed.
Time Cycle (destroyed)
Rook's Proto-TRUK was rebuilt into a Time Cycle by Ben 10,000 as UpRigg. However, it was destroyed.
Gwen's Spellbook (temporarily)
Rook used Gwen's Spellbook to cast a spell, teleporting Charmcaster to Ledgerdomain. He mentioned earlier in the episode that Gwen suggested that he carry some magical supplies with him in case of emergency.
Since Gwen was seen with her spellbook later, it would mean that she was just lending him her spellbook.
Rook can't handle high temperatures for long periods of time, due to having fur.
Rook does not like beam scans as the Z bosons condense on his fur, making him itch.
Rook is a 'by-the-book' Plumber and at times can be too rigid. As a result, he can sometimes be at a disadvantage when facing against an unpredictable foe and needs to 'think-outside-of-the-box'.
Due to being relatively new to Earth customs and culture, Rook is sometimes confused with expressions and Ben's unorthodox style of handling certain situations. At times, he takes certain expressions literally.
Rook is somewhat naive and overly trusting, which can lead to misunderstandings or awkward situations.
Original Series Aliens
Reboot Series Aliens