Yes, "Cowboy Bebop: The Movie," titled "Cowboy Bebop: The Movie - Knockin' on Heaven's Door," is set in the same universe as the original "Cowboy Bebop" anime series. It takes place between episodes 22 and 23 of the series, though it can be watched independently. The film features the main characters—Spike, Jet, Faye, Ed, and Ein—on a mission to capture a terrorist who threatens to unleash a deadly virus. Its themes and character development align with those of the series, making it a fitting extension of the story.

"Cowboy Bebop: The Movie," officially titled "Cowboy Bebop: Knockin' on Heaven's Door," is not strictly necessary to understand the main story of the anime series, as it stands alone with its own plot. However, it enriches the universe and deepens the characters' backstories, particularly exploring themes of loss and existentialism. Fans of the series may find the movie a rewarding addition, offering more of the show's unique blend of action, music, and emotion. It's recommended for those who enjoyed the original series.

"Cowboy Bebop: The Movie," also known as "Cowboy Bebop: Knockin' on Heaven's Door," is set within the timeline of the original anime series and is generally considered canon. It takes place between episodes 22 and 23 of the series, featuring the same characters and maintaining the show's thematic elements. However, some fans view it as a standalone story that enhances the universe rather than a critical component of the overall narrative. Nonetheless, it is widely accepted as part of the "Cowboy Bebop" canon.

"Cowboy Bebop: The Movie" struggled at the box office for several reasons. Despite its critical acclaim and strong fan base from the anime series, it faced limited marketing and a release in a competitive summer season in 2003. The film was also targeted primarily at a niche audience, which may have limited its appeal to mainstream viewers. Additionally, it was released in a time when anime films were not widely recognized in theaters, contributing to its underperformance financially. Overall, it didn't resonate enough with a broader audience.