In Ringworld, Speaker-to-Animals is a junior diplomat who is trained to deal with other species without reflexively killing them. He is recruited by Nessus, a Pierson's Puppetteer, as a member of an expedition to explore the Ringworld.
In the sequel The Ringworld Engineers Chmeee, along with Louis Wu, is kidnapped by the Hindmost (the exiled leader of the Puppeteers). The Hindmost wants Louis and Chmeee to uncover the secret behind the creation of the Ringworld. Chmeee escapes and manages to conquer the Map of Kzin and become its new leader.
As a member of the Kzin species, Speaker-to-Animals is extremely dangerous and always ready to fight despite the fact that he is a diplomat. He was the one that caused the most damage to the Ringworld village of Zignamuclikclik and were he not a part of the Docile Kzinti project, he probably would have leveled the village to the ground. He is also responsible for the expedition's safety on Ringworld and therefore is in charge most of the time.
Chmeee was badly burned during Ringworld; and as a result, his body was covered with scars. After involuntarily receiving an injection of the Kzinti analog of boosterspice, his scarring gradually disappeared.
Warlike: Chmeee is very warlike. He is always on guard in case he is attacked. There are numerous examples in both novels he appears in where he sees things as weapons first, tools second. Early in the second novel, he gored Louis Wu by accident when Louis shook him awake. Chmeee is a fantastic fighter and will kill without a second thought.