We propose a model in which agents have attitudes and expectations about a political issue or a proposed policy. They are the result of their mental model, which specifies the perceived causal structure of the relevant economic and political system, and their values that determine whether the expected outcomes of a policy are desirable for the agent or not. The privately formed attitudes and expectations respond to narratives told by other agents. A narrative is defined here as a story about a publicly discussed policy that contains both an expectation about the policy’s outcome and the desirability of that outcome. We show how a single narrative initiator can affect the median attitudes and expectations of a large group.