This research seeks to furthering understandings of how Tour Guides interpret memories at heritage sites when the memories at issue are difficult yet subtle and not always apparent to tourists. Specifically, it explores how Dublin Castle, formerly the seat of British rule in Ireland, is captured in narratives presented to tourists that often include Britons. Representing the site is made challenging because some visitors have little knowledge of the site's history, while others are well informed and hold strong political views. The findings show that Guides select largely depoliticized narratives, strongly influenced by their personal interests and experiences. Some hint at underlying tensions that only tourists alert to the complexities of the site might capture. Dominant narratives can be challenged by tourists with an interest in, or allegiance to, particular historical or political beliefs, leading to emotional engagements. Some tourists, unaware of the complexities of the site, can encounter a more multi-layered and complex experience than perhaps envisaged. The study affirms the co-production evident in Tour Guiding narratives and points to the need for further research into how the variously empowered agencies of both the Guide and the tourist produce a constant shifting and re-working of memory.