At the beginning of the original film, Roger is a bachelor songwriter, who lives in a small bachelor flat with Pongo. He works from home, usually not quitting work until after 5:00, and is described by Pongo as being married to his work. As a songwriter, he is very creative, and can easily write lyrics when given proper inspiration. However, it is only at Pongo's insistence that Roger meets Anita, as Roger would have stayed a bachelor forever according to Pongo.
After his marriage, he is shown to be a kind man who cares for his family, including his pets. Roger is not afraid to stand up against Cruella when his family is involved. A scene near the end of the film shows that he is good at mental math, as he is able to tally up the number of Dalmatians fairly easily.
Roger is based on the character of Mr. Dearly from the original book The Hundred and One Dalmatians by Dodie Smith. In the book, Mr. Dearly plays a similar role to Roger but is a financial wizard rather than a songwriter.
At the beginning of the film, Roger is seen working on a song. Pongo, having grown bored with their bachelor lives, conspires to set his pet up with a girl. After seeing Anita and Perdita, Pongo decides they would be perfect, as they were both beautiful. Pongo sets the clock ahead so that Roger believes that it is time for their walk. Roger is then forcefully dragged along as Pongo attempts to get Roger and Anita to meet. Eventually, Roger and Anita end up in the pond of the park, entangled by the leashes of their dogs. Roger attempts to apologize to the upset Anita, and blaming Pongo for making her wet, but the two end up laughing. A time skip shows that Roger and Anita fall in love and marry, and the two settle in a small house near the park with Pongo, Perdita, and Nanny.
Some time later, Roger is writing a new song but has only managed to get the melody written. He gains inspiration for lyrics after hearing the name of Cruella De Vil, Anita's former classmate. While Anita visits with her "friend," Roger writes a mocking song, relating the name to many frightening images. Three weeks later, Perdita is preparing to give birth to puppies. Roger is shown to be just as nervous as Pongo during the process, such that he jumps when Pongo licks his hand. He is initially overjoyed at the prospect of 15 puppies but saddens after hearing that one died. However, Roger is able to revive the puppy by rubbing it. When Cruella returns, intent on buying all the puppies, she mocks Roger’s song, which annoys him. Roger stands up firm to her, informing Cruella that they will never sell the puppies for any price. Cruella is angered to the point that she storms off, threatening to get even. However, both Anita and Nanny call him a hero.
One night, Roger and Anita take Pongo and Perdita out for a walk in the park. While they are gone, the puppies are stolen by Jasper and Horace Badun, hired hands working for Cruella. Roger is shown to be saddened by the theft. He suspects Cruella's involvement, but neither he nor the police are able to connect her to the crime.
That same night, while on their usual walk in the park, Roger becomes annoyed at Pongo's constant barking and forcefully drags him home, unaware that Pongo was actually passing the message of the puppies' theft through the Twilight Barking Chain. Roger punishes Pongo inside the house for disturbing the neighborhood, but Pongo finds a way to get out is the dog door to reach the Great Dane, named Danny who received the message.
Roger is seen near the end of the film, around Christmas time, wondering why Pongo and Perdita had run away (unknown to him, they had gone to rescue the puppies). After hearing his Cruella song on the radio, he turns it off. It is revealed by Anita that the song had become Roger's first big hit, and had brought in more money than they could dream of. When a group of "Labradors" come bursting into the home, Roger is confused, but he quickly realizes that they are actually Pongo, Perdita, and the puppies. Roger soon realizes that there are more than 15 puppies, and as Anita and Nanny find puppies, he adds up the totals to reveal that there are 101 Dalmatians altogether. Together with Anita, he decides to use the royalties from his songwriting to buy a country home big enough to keep all the puppies.
Roger is shown packing up for their move to their new country home when seeing the spots from a large number of puppies inspires him to write a new song "Seeing Spots". Later, after moving to the country home, Roger is trying to adjust to his new life when he notices the newspaper showing a photo that includes Patch, causing him to realize that they have accidentally left the puppy behind during the move, and the adults frantically travel back to London in their car to retrieve him. They succeed in doing so at the end of the film and Jasper and Horace then confesses to him it was Cruella who was behind the dognapping theft. During the credits, a newspaper clipping shows that Roger's new song "Seeing Spots" wins him an award on music.
Roger appears in the series along with Anita and Nanny. This version of Roger is a combination of the musician version from the animated movie and his game-developer version from the live-action film, as he is shown working in both professions. He's also depicted with brown hair instead of blond. He is always aware of Cruella's evil schemes to get him to give up the farm.
He and Anita also made a few appearances in the animated series House of Mouse, in crowd shots.
In the live-action remake of 101 Dalmatians, Roger's last name is changed to "Dearly" (which was his last name in the original book), and he is the human protagonist. Here, he is an American citizen, but he lives in a British flat with Pongo. Instead of a musician, he is a video game maker and tests how good the game is through his greatest friend/boss's son Herbert.
Roger's initial life is bachelorhood, and he can't afford a vehicle but uses his bicycle as transportation. He also lives in a one-room apartment home with Pongo who has a mind like a human but cannot speak English. The news breaks out that one of the rare Siberian tigers has been stolen from the zoo and that nobody has seen any trace of it.
Roger first ends up meeting Anita by accident. When Pongo sees Anita's Dalmatian; Perdita, he falls in love instantly and when Roger prepares to go back home, Pongo runs so fast after Perdita, dragging Roger dangerously throughout the streets on his bike. While Roger screams in fear, Pongo's actions cause car pile-ups on the roads and eventually the leash snaps apart causing Roger to crash his bike into a lake. A furious, injured Roger follows Pongo without a shoe and on his wrecked bike. However, he confuses Perdita to be Pongo and leashes Perdita, but is in return struck by Anita's purse full of bricks, causing his body to fully be injured. Eventually, they clear up the misunderstanding (and Roger takes the opportunity to remark that thanks to Anita, he "now got the complete set of bodily injuries"). But as they prepare to part, Perdita drags Anita just as Pongo did to Roger hinting their love. Eventually, both dogs and Anita and Roger marry and move to a small house near the park while hiring Anita's childhood nanny as a maid.
One day, Anita's boss; Cruella De Vil visits them to introduce herself to Roger. Initially, Roger is pleased to meet her but Roger's respect for Cruella slowly drains out into anger and frustration when Cruella spends the visit's time mocking Anita for starting a family, boasting about her wealth, her sarcastic sense of humor, and mocking Roger's career as a video game maker. Cruella learns that Perdita is giving birth to puppies in a few months and vows to come back.
Indeed, Cruella returns when the puppies are born. Before she arrives, one puppy nearly dies from an unmentioned infant issue but Roger uses a CPR method to save its life and names the puppy "Lucky." When Cruella returns, she has gone insane with her obsession with furs. She immediately offers to purchase the puppies when learning that the spots will be formed in a few weeks. However, Roger angrily refuses to sell them no matter what even if she offers any money to them. Anita tries to keep her relationship with Cruella by claiming that they do not mean immediately but she ultimately gains the courage to stand up against Cruella and agree that they are not for sale. A furious Cruella leaves firing Anita from her fur factory and vowing revenge.
A few months later, the puppies have finally gotten their spots. While Roger and Anita go on a date taking Pongo and Perdita with them, two bandits named Horace and Jasper break into the house, restrain Nanny, and lock her in a closet. The bandits then steal the puppies and drive off. Roger and Anita figure out what has happened when they return (when they hear the Pensioner's bulldog barking angrily at Horace and Jasper and is the witness), realizing what they did leaving the puppies unprotected and call the police. Unlike the 1961 movie, however, Roger and Anita do not suspect Cruella immediately; and Anita does not refuse to investigate Cruella for their relationship.
The next morning, Pongo and Perdita flee the house in the eyes of Roger and Anita when a message from the other dogs informed them where the puppies are. This time, Roger and Anita are unable to stop them and are now worried for their two Dalmatians. They also ask the police to set up a police chase for Pongo and Perdita.
After 3 days finally, Anita and Roger find out the culprit of the 15 puppies theft through Anita's quick thinking. Anita reveals to Roger and the police that when she worked for Cruella as a fur coat designer, she made a design of a Dalmatian coat for fun and that Cruella stole the puppies hoping to kill them and make a spotted fur coat out of them. The Dearlys go to Cruella's factory with the police where they connect Cruella to other crimes, such as the missing Siberian tiger. The two sadly hug, regretting going out for a date with Pongo and Perdita instead of staying home to keep an eye on the puppies.
Not long afterward, the police find the 99 Dalmatian puppies, Pongo and Perdita in a village in the outskirts of London. They also manage to find and arrest Cruella, and her henchmen Jasper, Horace, and Skinner. Roger and Anita decide to adopt all of the 84 puppies leaving them with a total of 101 Dalmatians. When Roger reads the paper and hears that the criminals have been convicted of the crimes, including their puppies' thefts, he gets inspired and makes a new video game of Dalmatian puppies fleeing from Cruella, who is the antagonist/boss of the game. The game is a worldwide success, and Roger is now a billionaire and father to a baby girl. Roger uses his money to buy a giant mansion and barn on the outskirts of London.
- In the novel, the surname of the Dalmatians' humans is "Dearly", but was changed to Radcliffe for the animated film; most likely because Disney has a number of families in previous films with similar names, such as the Darlings from Peter Pan and Jim Dear from Lady and the Tramp. Their surnames return to being Dearly in the live-action films and 101 Dalmatians: The Series.
- In the first animated film, Roger shares the same speaking voice actor with Grimsby in The Little Mermaid, known as Ben Wright, but his singing voice is done by Bill Lee of the Mellomen.
- Both of Roger's original voice actors participated in the movie version of The Sound of Music with Wright portraying Herr Zeller (meaning "Mr. Zeller" in German) and Lee dubbing over Christopher Plummer's singing as Captain Von Trapp.
- Hugh Grant was considered to play Roger for the live-action remake of the film before Jeff Daniels was cast as Roger instead.
- Roger is often seen smoking a pipe in the animated films, but in the animated series, he is not seen with a pipe (though, while this may be due to censorship, Lucky and Anita do mention that Roger did smoke a pipe prior to when 101 Dalmatians: The Series was set).