Tracy is a passionate young hamster whose compassion for others never let her ignore those in need or keep quiet when witnessing injustice. This caused friction with her mother, a traditionalist in the century-long war raging between hamsters and mice, and eventually Tracy left/was kicked out of her home. Her old friends Gwenendale Griggs (whom Tracy had developed a teen crush on) and Oswald Irving, homeless as well, took her in as they worked to get by. Tracy's idealism would eventually result in the creation of the band HamstaPowah and their songs on equality, with Tracy as their pianist and lead singer.
Story Summary (Spoilers Beyond This Point)
The HamstaPowah band are preparing for their last gig of the concert year. The show goes well, but during their performance a young mouse boy breaks into the building, on the run. After a bit of help from the band, the mouse slips and falls, but is caught by J'Aime Beck, the band's number one fan who is helping out backstage to attend the show with some of her friends. Mark Hamsta is skeptical about the boy, and discovers a mark on his shoulder that indicates he's from a human lab, but Tracy is adamant about helping the poor young boy, who seems lost and confused. The rest of the band agrees, and she adopts him and decides to name him Darin Starr, as he seems unable to talk.
After the show, the band are on their way back to their out of town residence, riding atop their cat Bobo, when a strange robotic machine attacks them. Bobo is stunned by an electrical attack and everyone else is sent flying, including Tracy, who misses most of what follows. The robot first tries to capture Sarai Kerice, a young most who, along with her mother Kamilia Kerice, has been taken in by the band as paid workers after Sam freed them. Darin however intercepts it, demonstrating an odd power and fending it off briefly before being overcome. This buys time for Mark and Bobo to attack the robot, landing a lucky hit on its weak point that destroys it. Tracy finds Darin with Sarai, the former battered and out cold but not badly hurt, and everyone else is intact, so they quickly head home in case more robots show up.
Later on, while the band are doing errands in Crosond, the city is beset by an army of robots like the one they faced. Aside from Snowbell Crystal, they manage to keep out of the way this time, and Mark finds Darin, who was caught up in things again, so they take him back to their home to recover. Later still the band hears news of an explosion of unknown cause that has wiped out part of the red district of the city, causing them all to worry for their friends.
Sarai goes to check on Darin, and when the others hear a mysterious thump from the roof, they head up to investigate. Arriving on the roof, they see Darin standing in a strange symbol marked out in chalk, and are unable to stop Sarai stepping onto it, which causes them to vanish in a pillar of light that bursts from the symbol. Sarai is taken to a strange realm where she is shown Darin's memories, the others witnessing the same images projected on the pillar of light. They see the human scientist who claimed full responsibility for the attack, Darin's condition, and a plan to revert the non-human species, allowing them to piece together far more of the puzzle. Lastly, Darin appears lucidly, asking for their help stopping him, before passing out again in exhaustion. As everyone turns in after a very draining day, Tracy tucks in Darin, making sure he's fine and alright before leaving him to sleep.