Ari bn Bem, an honorary commander from Pandro, whose interference as an observer endangers the Enterprise landing party in Bem.
Commander Ari bn Bem is a representative of Pandro, a newly contacted planet, serving as an independent observer of the Federation aboard the Enterprise in Bem. Pandronians are colony creatures whose bodies can separate into independent parts.
Bem accompanies a landing party to a newly discovered planet but interferes rather than observing, and Kirk's party is captured by the natives. They learn that a powerful non-corporeal entity is guarding the natives as its children. Bem eventually recognises his error and the entity allows the Enterprise to leave.