Danganronpa: Trigger Happy Havoc is a visual novel adventure game developed and published by Spike. The first installment in the Danganronpa series, it was originally released for the PlayStation Portable in Japan in November 2010. It was ported to Android and iOS in August 2012. NIS America localized and published the game internationally on PlayStation consoles.

The player controls a high school student named Makoto Naegi who finds himself involved in a battle royale in Hope's Peak Academy, where the robot bear Monokuma gives the students the chance to escape from the establishment if they murder another student and are not voted as the killer in a trial. Combining elements from dating simulations and third-person shooters, the game sees Makoto interact with other students to solve "class trials" by shooting at arguments displayed on the screen.

The game originated from writer Kazutaka Kodaka's idea to generate a new type of game, as he believed the original adventure games were no longer popular. As a result, he created a dark scenario that generated controversy within Spike due to the amount of violence displayed among students. Nevertheless, the company decided to develop it alongside the unique gameplay system which they thought was less derivative from other games. The cast was designed by Rui Komatsuzaki.

Danganronpa was a commercial success and earned positive reviews for the handling of the cast and story. It won awards, though critics were divided on the lack of challenging difficulty in solving class trials and its mini games. A sequel, Danganronpa 2: Goodbye Despair, was released in 2012. A compilation of both games, titled Danganronpa 1・2 Reload, was released for PlayStation Vita in Japan in October 2013, and worldwide in March 2017. The game produced several adaptions and spin-offs: an anime television series, a stage show, two manga, and two novels.

Danganronpa: Trigger Happy Havoc is a murder mystery game that casts players in the role of Makoto Naegi, a student of Hope's Peak Academy who finds himself trapped in a game of mutual killing among his peers. The gameplay is stylistically similar to Capcom's Ace Attorney series by being centered around investigation and finding contradictions, albeit with an emphasis on faster gameplay. Each chapter of the game features two styles of gameplay: School Life, in which the player explores the academy and progresses through the story, and the Class Trial, where the player must determine the culprit of a crime.

During School Life, the player can explore the school grounds in first-person perspective, with more areas of the academy becoming available as the game progresses. Whilst in one of the various rooms, players move a crosshair cursor which is used to initiate conversations with characters or examine parts of the environment. Examining certain objects yields Monokuma Coins, which can be used at a capsule machine in the school shop to unlock presents. School Life is divided into two sections: "Daily Life" and "Deadly Life". In the Daily Life sections, players converse with various characters and move the plot along based on dating sim elements. New information can be revealed by "reacting to" certain comments. In designated "Free Time" segments, players can choose to hang out with specific characters and give them presents, which in turn reveals more information about them and unlocks various Skills that can be used in the Class Trials. When a crime scene is discovered, the game shifts to the Deadly Life section, where the player must search for clues throughout the academy. Evidence and testimonies gathered are stored in the player's e-Handbook, where players can also save their game. When all possible evidence is located, the game moves on to the Class Trial. Prior to a Class Trial, players can purchase skills, which can assist them during gameplay.

The Class Trials occur following the discovery of a dead body. Within them, the students discuss amongst themselves who the culprit is. With the exception of occasions where the player must answer a multiple choice question or present a piece of evidence, Class Trials consist of four main modes of gameplay: Nonstop Debate, Hangman's Gambit, Bullet Time Battle, and Closing Argument. In the Nonstop Debate, characters discuss their thoughts on the case, with potential "weak points" highlighted in yellow. During these sections, the player is armed with "Truth Bullets" based on third-person shooter gaming: metaphorical bullets containing evidence relevant to the discussion. In order to "break" the debate, stopping it from going on indefinitely, the player must find a lie or contradiction amongst the weak points and shoot it with a bullet containing the evidence that contradicts it. Players can also silence disruptive purple chatter to earn extra time and utilize a Concentration meter to slow down the conversation and make shots more easily. Trials occasionally require the player to absorb a classmate's remark and use it as ammunition against another. Hangman's Gambit is a shooting puzzle section in which the player must shoot down specific letters that spell out a clue. Bullet Time Battle is a one-on-one debate against another student featuring rhythm style gameplay. As the opponent makes remarks, the player must press buttons in time to the beat to lock onto the remarks and shoot them down. Finally, Closing Argument is a puzzle in which players piece together a comic strip depicting how a crime occurred. The player's Influence amongst the other students is represented by hearts, which is reduced whenever the player makes errors in shooting contradictions or presenting evidence, and is replenished when correct evidence is presented. The game ends if the player loses all of their Influence, or if they run out of time during a segment. At the end of a trial, players are ranked on their performance, with additional Monokuma Medals awarded for high ranks.

From the PlayStation Vita version onward, the game features an additional School Life mode, based on the Island Mode introduced in Danganronpa 2, which is unlocked after clearing the game once. In this alternative mode, Monokuma tasks the students with building several backup units of himself over several days. Each day, the player assigns students to scavenge rooms for necessary materials needed to build each concept, keep the school clean, or rest up to recover energy. During Free Time, players can either hang out with the other students to unlock skills just like in the main game, or use Trip Tickets earned from completed concepts to take them on trips.