In one aspect, an example method includes (i) obtaining a set of user attributes for a user of a content-presentation device; (ii) based on the set of user attributes, obtaining structured data and determining a textual description of the structured data; (iii) transforming, using a text-to-speech engine, the textual description of the structured data into synthesized speech; and (iv) generating, using the synthesized speech and for display by the content-presentation device, a synthetic video of a targeted advertisement comprising the synthesized speech.