A youth novel from the 1970's. Two Earth guys and a girl are space/science academy students. Earth is just developing a star drive engine. They are chosen for a planet survey mission as guests of an advanced alien group. They are disguised as members of one of three native races and accompanied by an alien guide who is disguised as a humble "pet" being called a Bundii. He is a member of an Earth religious sect that promotes intergalactic peace and harmony - he is trying to tame his temper. One other race on the planet is a shark-like humanoid. They have also developed the same technology but do not realize it is a star drive. They think it is only a killing device. The test is whether the humans will reveal that it is a star drive machine to the "sharks" who are a less advanced, warlike race. They do not, and humans are welcomed into the alien community as fellow members of the civilized worlds. Whazis?