The design of a narrative video game for cognitive training of memory and executive functions in older adults with subjective and objective cognitive impairment is reported along with preliminary results on preferences (Study 1), user interaction experience (Study 2), and efficacy of the game (Study 3). A study of aesthetic preferences in backgrounds and avatars was implemented in 13 older adults, who were asked for their opinion on the acceptability of the plot. After completion of the design, a user interaction study was conducted in a sample of 19 older adults. In addition, a Matched Paired Experimental Design (MPED) was implemented as a preliminary test of the efficacy of the narrative video game in a sample of 22 participants with Subjective Cognitive Decline (SCD) and Mild Cognitive Impairment (MCI). Preferences for free violence content in videogames was supported in our sample of low-frequency adult gamers and acceptability of the plot was high. The video game was rated favourably by the older adults in terms of user preferences and acceptability. The results of the preliminary MPED study suggest that the video game could be a useful tool for cognitive training in SCD and MCI older adults.