NEXT: THE PORTOPIA SERIAL MURDER CASE

Released for free on Steam on April 24, 2023, *NEXT: THE PORTOPIA SERIAL MURDER CASE* is Square Enix’s AI Tech Preview of a landmark Japanese detective game. It revisits *The Portopia Serial Murder Case*, written by Yuji Horii and first released in 1983. Rather than presenting a new mystery, NEXT uses the earlier game’s investigation to demonstrate a different way of entering commands: players can address their police assistant, Yasu, in ordinary language. That choice links a modern experiment in language recognition to a title whose original text-command interface was itself a distinctive part of playing the detective.

The case begins with the death of Kozo Yamakawa, found in a locked room. The player takes the role of the detective directing the investigation, while Yasu carries out instructions, examines locations and speaks to people connected with the victim. Progress depends on noticing details and deciding what to ask or investigate next. NEXT preserves this arrangement: the player does not walk freely through a three-dimensional reconstruction of the crime scene, but guides Yasu through a sequence of scenes and exchanges. The central challenge remains working out how the clues fit together, not winning a fight or building a character.

Square Enix’s stated focus for NEXT was natural language understanding. In a conventional adventure game, the player might select a fixed command or struggle to guess the precise words accepted by a parser. Here, the system attempts to interpret a wider range of typed requests and map them to actions and dialogue available in the game. The release also includes speech recognition, allowing spoken input. These features make Yasu the visible point of contact between the player and the technology: an instruction only advances the investigation when the system understands what the player wants him to do.

The “AI Tech Preview” label matters. Square Enix said it had considered using natural language generation to produce replies, but omitted that feature from the release because of concerns about inappropriate responses. Yasu’s replies are therefore not an unrestricted, AI-written conversation. NEXT is better understood as an experiment in interpreting player instructions within an existing detective story. Its historical connection is unusually direct: it returns to a Yuji Horii mystery from 1983, four decades later, and tests whether newer language technology can make giving orders to Yasu feel less like finding the correct command and more like conducting an investigation.