GTA–NarrativeTraj is presented as a simulation framework and dataset for Grand Theft Auto V (GTA V) that couples spatiotemporal trajectories with in-game narrative signals (speech audio, subtitles, speaker identity). A ScriptHookVDotNet-based logger records world coordinates and vehicle state at ≥ 1Hz and captures dialogue events (subtitle text, speaker tags, soundbank IDs) during story-mode play. The released dataset provides tightly time-aligned GPS-like traces and the complete dialogue stream for full playthroughs, yielding a resource in which coordinates, audio, and text jointly form a narrative constraining and explaining agent motion. The task of narrative-grounded mobility prediction is introduced: given recent GPS and ongoing utterances, infer the agent’s near-term path and next waypoint while recovering salient context such as interlocutors (who is speaking to whom), scene-level locations, and dialogue-implicated points of interest. The dataset serves as ground truth for these tasks by pairing GPS histories with contemporaneous narrative cues and future motion outcomes - enabling models that reason simultaneously over movement, interlocutors, and places. Reproducibility, offset stability, and licensing are discussed; the release includes code, logs, transcripts, and time-aligned audio features, while excluding raw copyrighted assets.