Honestly, the Comedy Central movies for Futurama were the only misstep the series took. First came Bender's Big Score, then this entry landed... To mixed success. All the comedy and sci-fi nods are there, but the movie gets bogged down a little by the plot.
Without including spoilers, another love interest of Fry's steps up to the plate, while an invincible intergalactic entity terrorizes the universe by turning everyone into a single concentric cult being. The problems start midway through when there's just too much shipping drama between the antagonist, the villain, and the supporting cast. Futurama is a series of quips, cutaways, and social commentary. It is not a series that focuses on getting bogged down in Emo feels. Beast With a Billion Backs does the later while nearly avoiding the former in the second act.
It also is DVD only, which while beautiful in 2007 now looks a little dated. Especially compared to the later two of the four movies, which released on Blu-ray shortly after this came out.
Still, the movie is perfectly enjoyable even if it's not relatable. Slightly recommended for casuals. Definitely recommended for series enthusiasts.