What are you trying to do!?! Kill me!?!
~ Arno to his henchmen when they accidentally endanger him.

Applejack "A.J." Arno is the main antagonist of the Dexter Reilly trilogy. He is a corrupt businessman and the mastermind behind several illegal operations in the town of Medfield, Massachusetts. He is the archenemy of Dexter Reilly, the protagonist of the trilogy.

He was portrayed by the late Cesar Romero, who also played the original Joker in the classic Batman TV show.


The Computer Wore Tennis Shoes

The students persuade wealthy businessman A.J. Arno to donate an old computer to the college. Arno is the secret head of a large illegal gambling ring, which used the computer for its operations.

During the tournament, a trigger word causes Dexter Riley to unknowingly recite on television details of Arno's gambling ring. Arno's henchmen kidnap Riley and plan to kill him, but his friends help him escape. Arno's home is being painted, and in the rescue effort, Riley's friends put paint in the gas tanks of the henchmen's cars, causing them not to start, and following a brief chase in his own car, Arno ends up in a pile of hay.

During the escape, Riley suffers a concussion which, during the tournament final against rival Springfield State, gradually returns his mental abilities to normal; however, one of his friends is able to answer the final question ("What is the geographic center of the contiguous United States?"). Medfield wins the $100,000 prize. Arno and his henchmen are arrested when they attempt to escape the TV studio and crash head-on into a police car.

Now You See Him, Now You Don't

As Dexter examines his burnt equipment with dismay, Higgins meets with Arno who has recently purchased Medfield's mortgage. When Dexter accidentally drops one half of his protective glasses into a container of his experimental formula, it appears as if the substance destroys them, but upon closer examination, Dexter realizes the frames are merely partially invisible. After several excited tests, Dexter boldly places his fingers in the liquid and they disappear. Schuyler and Debbie arrive and are horrified to see Dexter with a partial hand, but Dexter insists Schuyler test the substance as well, admitting only afterward that he does not yet have an antidote. Just then, Higgins brings Arno to visit the lab, stunning the students, as only two years earlier, Dexter was instrumental in exposing Arno's crooked gambling scheme. Although distracted by the condition of their partially visible hands, Dexter and the others notice that Arno is more concerned with the campus architecture than Higgins' curriculum speech. After Arno and Higgins depart, Dexter and Schuyler discover, to their surprise, that water washes off the invisibility formula's effects. Curious about Arno's behavior, Dexter convinces Schuyler to use the invisibility formula to sneak into Arno's office that night to look around. Although they are nearly discovered when Schuyler steps into a puddle, making his tennis shoes visible, the boys get inside Arno's office where they find a model of Medfield College redesigned as sprawling gambling establishment. After taking photos of the model, the boys flee with Debbie's help.

The next day, Dexter shows the photos to Lufkin and Higgins, both of whom are alarmed and concerned about how to buy back the college's mortgage. Convinced that Druffle's bumblebee study would draw attention and investments to Medfield, Higgins reacts angrily when Dexter assures him that his invisibility formula could win the top prize money in the upcoming Forsythe science contest. Not having admitted to anyone that Medfield has been dropped from the contest for being too insignificant, Higgins determinedly contacts the contest's sponsor, millionaire Timothy Forsythe and agrees to meet over a game of golf, despite his inability to play. Upon learning of Higgins' plan and suspecting it must be connected with raising money for the college, Dexter urges Schuyler to volunteer to serve as Higgins' caddy while, hidden by the invisibility formula, he will take control of Higgins' golf ball. At the golf club, Forsythe and the state university dean, Collingsgood, are amazed by Higgins' quirky golfing abilities, which include numerous hole-in-one-shots, as is Arno who is also at the club. After the game, Forsythe enthusiastically agrees to reinstate Medfield into the competition for the Forsythe Award. Meanwhile, Arno accidentally sees Dexter becoming visible in the club showers and grows suspicious. When the local television news covers Higgins' extraordinary golf game, he is invited to join an exclusive tournament in nearby Ocean City. Convinced that he will win enough money to pay the college's mortgage, Higgins brashly accepts and that afternoon departs with Schuyler. Learning of the tournament from Druffle too late, Dexter misses the plane and is forced to watch the competition on television where Higgins' game against two professionals is a disaster. In his business office, Arno and his henchmen, Cookie and Alfred, also watch the tournament and ponder Higgins' odd inconsistency.

That evening, Cookie, disguised as a janitor, sneaks into the campus lab where he witnesses Dexter and Schuyler using the invisibility spray, and reports to Arno, who orders him to return and steal it. The following day, Forsythe and members of his committee arrive on campus to judge the best science experiment at the college. Unaware that their spray bottle has been replaced by Cookie, Dexter and Schuyler make their presentation and are stunned when it has no effect. Disappointed and angry, Forsythe and Higgins depart as Dexter remains confused until he chats with Charlie, the janitor. Learning that there is no night janitor, Dexter realizes that Cookie was a spy and likely stole the formula. Concluding that Arno must be behind the theft, Dexter plants a walkie-talkie in his office.

A couple of days later, Schuyler overhears Arno plotting with Cookie to rob the Medfield Bank by making themselves and the money invisible. Certain that if he could retrieve the formula before the Forsythe Award announcement that night he could still win the contest, Dexter sends Schuyler to the police and goes to inform the bank's president, Wilfred Sampson. When both the police and Sampson dismiss the boys' story about invisibility, Dexter and his friends gather outside of the bank to make plans. While an invisible Arno and Cookie knock out the guards and take the money, Dexter unsuccessfully tries to use a fire hydrant to hose the men down as they exit the bank. When Sampson realizes a theft has occurred, he contacts the police who join the college students in a wild chase of the car driven by the invisible robbers.

After briefly eluding everyone, Arno orders Cookie to make the car invisible, but they are spotted on a dirt road in a park. Deducing Arno will not leave town but go to his home instead, Dexter drives there and forces Arno's car into a neighboring pool where it, the money, and the men become visible. Arno and Cookie are arrested at the scene and taken off to jail.

The Strongest Man in the World

After Harry informs Krinkle about the formula and agrees to steal it for $200,000, he drives to the state prison and hires Arno to steal the strength formula. Cookie is reluctant, but Arno allows Cookie to plan it. The following night, Arno and Cookie arrive at the college to find the halls crawling with security guards, but Cookie plans to get in to the laboratory by using a scaffold. After a truck dumps a load of wet cement, Arno and Cookie climb to the roof, only to find Arno has acrophobia. As Cookie lowers the scaffold, he hits a knot in the rope that almost tips them over. Once inside, Cookie is unable to find the formula and Arno regrets his decision of having Cookie as his leader. He opens a door to find a sleeping guard, who awakens and blows a whistle. As the other guards arrive, Cookie and Arno leap back onto the scaffold, but Arno hits the down lever and they fall, and when the guards look out the window, they only see their impressions in the wet cement below.

Unable to get back on campus, Arno and Cookie kidnap Schuyler to force him to reveal the formula. However, the Schuyler cannot remember all the ingredients. The thieves take him to a Chinese restaurant where the chief of police is giving a speech. In a back room, the restaurant's owner, Ah Fong, hypnotizes Schuyler into reciting the formula, then gives him a post hypnotic suggestion to forget everything and take the first mode of transportation he sees to get home, which results in him getting arrested by the police after stealing the chief's car. Dean Higgins bails him out, but Schuyler doesn't remember anything.

The next day, Krinkle drinks Schuyler's formula. To demonstrate his new strength, he takes karate chops at the conference table and breaks his hand. Harry convinces Krinkle that the fake formula is even better than the real thing as Harriet will be humiliated after the Medfield students eat her cereal on television and are soundly defeated by the State athletes.

The day of the match, Dietz warns Higgins that he will be fired if Medfield loses. In front of the cameras, the scrawny Medfield and the muscle bound State athletes eat the cereal of their respective sponsors. When no steam comes out of his ears, Dexter realizes something is wrong and deduces that that it was really his spilt formula that created super strength. After warning Quigley and Higgins, Dexter remembers he still has a test tube of his formula at the laboratory and borrows Higgins's Model T car. Harry overhears the conversation and telephones Arno to stop him. Dexter cannot get Higgins's car to go faster than a crawl. When he does get to the laboratory and finds the test tube, Arno and his henchmen arrive. Dexter gulps down the formula, then tosses the men around the lab. In the hall, Dexter finds Harry hiding, and rolls him like a bowling ball to knock the rest of the henchmen over. Running out of the building, Dexter hears the car radio announce that he is the last contestant and has four minutes to appear or Medfield must forfeit. Desperate, Dexter pours some drops of the formula into Higgins's car's radiator and it takes off like a rocket as Arno and his men try to catch him. He makes it in time to compete, but the car is a complete wreck, much to the dean's horror. Dexter uses the last of his super-strength to lift the 1111 pound weight and win it for Crumply Crunch and Medfield. Higgins and Quigley get to keep their jobs, Arno is imprisoned yet again, and Krinkle breaks his hand again after eating the wrong cereal.





  • There is a running gag in the series where Arno mispronounces Dexter's name.
  • Although Arno is the Big Bad of the franchise, Krinkle serves as the Bigger Bad in The Strongest Man in the World because he had bigger plans than anyone else.
  • Arno's character doesn't exist in the 1995 remake. Instead, he is replaced by a 12-year-old genius named Norwood Gills.


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