The "People" are Agent Epsilon's associates and employers, always referred to by characters as "my people", or "Epsilon's people".
Little to nothing is revealed about them during the course of the show, not even the true name of the organisation, but it is shown that they are a group all their own, distinct from the Secret Scientists. Like Agent Epsilon and Francis, they are "Grey Men", that is to say that have no adamant allegiances, and will do what they believe is necessary to ensure their personal goals. It is assumed by many characters in the show that the group works toward the general good, but that they approach that goal in a semi-Illuminati fashion, regarding their own view of what is right and wrong as above everyone else's, and taking routes that other more morally sensitive people might consider unorthodox. Epsilon's "People" are implied to have a command structure, ranging from field agents to the shadowy leaders that dictate every facet of the organisation's duties and lives.
In the episode The Unblinking Eye, Francis and Epsilon show that the agents are expected to follow the orders of their superiors with disregard for their personal feelings, something which Francis deeply resented. The organisation created a global positioning satellite to track Zak Saturday's movements utilizing the Naga Kur Detector for finding Kur, which they had stolen from Doyle's Swiss deposit box. They intended, unlike the secret scientists, to recruit Zak for their organisation, and train him to control his Kur powers alongside Francis, a factor which both Francis and Zak deeply disliked.