This paper presents a serious game for cultural heritage and in particular for museum environments focusing on the younger generation. The aim of the game is to solve a treasure hunt scenario by collecting medieval objects that used to be located in and around the Priory Undercroft. Located in the heart of Coventry, UK, the Priory Undercrofts are the remains of Coventry's original Benedictine monastery, dissolved by Henry VIII. Initial user testing demonstrated the potentials of serious games for education in museum environments. Game has been created using innovative aspects as far as 3D content reconstruction is concerned as well as educational scenarios. Thus, the main contribution of this paper lies in the direction of accelerating 3D reconstruction by combining computer vision tools and on the educational dimension of the developed game. In addition, artificial intelligence tools are adopted for conducting the plot of the game.