Quick Summary

(backstory)The book takes place in a land called Media, it was originally ruled by a magical queen, but the animals demanded equal rights even for those without magic, so she worked more on that than she technology. Behind her back there was a rebellion growing and they took over the technology, it went into a full out war of magic and technology, in the end the technology leader and the queen both die. So, the technology leader's sister takes position as queen and Media is based off tech.
A spider monkey named Curiosity sneaks into a castle and kills many including a jester, he also uses magic to make himself a jester's suit. He basically wrecks the castle, breaking lots of things. He kills the king with a magical cube that once belonged to the magical queen. The king turns into a red crystal heart, Curiosity tries to pick it up, but it rejects him. So, he smashes it and 5 shards fly across the land. 
Radio Star, a cat, gets a message that her sister, Frequency Star rejected a mission so she had to take it. Excited that it was her first mission she got into the carriage to get to the castle. Inside was a folder with briefing about the mission. She ends up with Pictures, and Video, they set out and for some reason are accepted by the shard near the castle, so they leave following the signal of the shards.
 They end up at a critter village Video had been to before, the leader tells them that all the guards dissipated after the spider monkey pretended to be a rat and joined as a guard. He ended up getting all the guards to fight among themselves. Faith, the village leader, says they are trapped in a cave under some spell, they get their first encounter with Curiosity as he leaps through the forest around the village, Video fights him but Radio stops her before she runs off. They travel to the cave and Video fights Curiosity again, he pushes her into a pit where the guards are, she ends up killing them all, and Curiosity flees. They take the shard from the cave and apologize to Faith.
They travel around Media and collect six of the seven shards, during the time Radio and Pictures grow close. Then Radio insists they stop at her aunt, Studio Star's, city for a festival. During the night the capitol finds out and it turns out the last signal went out, so Pictures and Video get mad. They are told to report back to the castle, so the next night they stop to sleep in a meadow. 
That night Radio confronts Curiosity in her dreams, he tells her he'll help her and will give her some of his powers, but she has to bring him the shards she has. The bag that carries the shards is taken care of by Video, so Radio does it carefully, but Radio wakes up and thinks that Curiosity was possessing her. Radio begs her to spare her, but Video doesn't believe her and kills her. Pictures wakes up to the commotion and is horrified that Video killed Radio, he reviles that he is evil and Curiosity comes to him, Curiosity tells Video that Radio wasn't possessed and talks about her innocence. 
Curiosity and Pictures run off to the castle and Studio comes, she finds out Radio is dead and is disappointed, but Video lies and says Curiosity killed her. They go to the castle after Pictures, and then find out they killed the surveillance crew, they go to the throne room and find Pictures and Curiosity fighting because Pictures was upset Curiosity let Radio die. Then the heart joins together, but Video attacks Pictures, she slashes his neck and tosses him into a fire. Curiosity kills Video out of anger, and the king appears. (end of book 1)