Bryan Lee O’Malley was born on February 21, 1979, in London, Ontario, Canada. He is a Canadian cartoonist and writer, best known as the creator of the Scott Pilgrim series. He is of Korean descent from his mother's side and of Irish and French-Canadian descent from his father's side. He initially studied Film Studies at the University of Western Ontario but left before completing his degree.

O’Malley began his career in comics before creating his own original works. He illustrated the miniseries Hopeless Savages: Ground Zero for Oni Press, written by Jen Van Meter, and also worked as a letterer on numerous Oni titles. His first original graphic novel was Lost at Sea, released by Oni Press in 2003. The story is a coming-of-age narrative about an eighteen-year-old girl on a road trip who believes her soul was stolen by a cat.

From 2004 to 2010, O’Malley worked on his most famous creation, the six-volume graphic novel series Scott Pilgrim, also published by Oni Press. The series follows the title character, a slacker and musician in Toronto, who must battle the seven evil exes of his new girlfriend, Ramona Flowers. The books integrate fantasy elements borrowed from video games and indie rock culture. The series was a critical and commercial success, earning O’Malley several awards including an Eisner Award, a Doug Wright Award, and a Joe Shuster Award.

The success of Scott Pilgrim led to multiple adaptations. In 2010, the live-action film Scott Pilgrim vs. the World was released, directed by Edgar Wright. O’Malley has spoken about the collaborative experience of the film adaptation, noting that he had to trust the creative team, while for later projects he took on a more direct role. In 2023, an anime adaptation titled Scott Pilgrim Takes Off was released on Netflix. For this series, O’Malley served as an executive producer, writer, and showrunner alongside BenDavid Grabinski, and the animation was produced by the Japanese studio Science SARU. O’Malley has described this as the first time he was the “boss” on a project, where he focused on being open to the creativity of the other artists involved.

Beyond Scott Pilgrim, O’Malley has created other notable original works. In July 2014, he released the graphic novel Seconds, published by Ballantine Books. He is also the co-creator and writer of the ongoing comic book series Snotgirl, illustrated by Leslie Hung. As of 2024, he has been developing a new graphic novel titled Worst World, which he has described as a story about Los Angeles with more anime influence than his previous work.

Music plays a significant role in O’Malley’s creative identity. The world of Scott Pilgrim is deeply embedded in early 2000s indie music culture, and O’Malley himself performs as a musician under the alias Kupek. He has stated that he creates playlists to get into the headspace of his projects, such as Canadian indie rock for Scott Pilgrim. His artistic influences include comics such as Calvin and Hobbes, Archie, and Jeff Smith’s Bone, as well as shonen manga, which he cites as an inspiration for the personality of Scott Pilgrim. O’Malley is recognized as a significant figure in comics for creating a work that successfully bridged the gap between indie comics, video game culture, and mainstream popularity, leading to a major film and anime adaptation.