Reverse Quantum Curse/Old
Developer(s) RosettaChiko (tbc)
Publisher(s) Nin
Platform(s) Nintendo 3DS Logo
PC (Steam-Powered)
Genre(s) 2D Platformer, mystery
Series Investigator S
Release Date(s) Nintendo 3DS:
25px-Flag of Japan 16 February 2012
Flag of South Korea 22 February 2012
25px-Flag of Europe 22 April 2012
25px-Flag of Australia 22 April 2012
25px-Flag of USA 1 May 2012

22 June 2012 (worldwide)

Mode(s) 1 Player
Age Rating(s) Esrb-teen-logo-lrg 12Rating CERO A
Media Included Nintendo 3DS Cartridge

Investigator S: Reverse Quantum Curse, 3DS version known as Investigator S 3D: Reverse Quantum Curse (探偵小:逆量子 Detective Esu: Reverse Quantum), is a mystery, 2.5D platformer for the Nintendo 3DS and PC through Steam. It is being developed by X-Scissor, as the first game in the Investigator S series. It takes place in Victorian England, where S and other members of The Agency struggle to protect the nation from the XGen Agency. They must solve several mysteries in order to protect each other.


The game follows S, a former orphan, and Daka, a child with abusive parents, as they become detectives travel throughout Victorian England, solving mysteries and defeating crime.

In Reverse Quantum Curse, the girls are offered jobs from The Agency, an organization from the future. After accepting, the two find themselves battling with the forces of XGen.

One day, an attack is launched on the base of The Agency. Kira claims that "this is the beginning of the end for the English". Boss A. goes to battle with Kira, but he is defeated quickly by Ranao. The girls go into a fight with the powerful man and defeat him.

Kira flees from The Agency momentarily. The girls head back to their normal jobs at their HQ. Until, one day, Boss A. calls the two in to talk to him. He tells that the two came from the future to stop Kira from taking over England, and he asks for the girls' assistance.

The girls accept their mission and head to the XGen headquarters. They encounter many mysteries throughout the labyrinth, until they make it to the end of the dungeon and must battle with Kirana. After defeating her, they approach Kira.

S is sent to the future by the powers of Kira. In the year 3005, S meets the new Agency, and tells her story. After obtaining a Cross Stopwatch, S is able to travel back to her time. She discovers that the entire Agency has been taken over by Kira.

While S is in the future, Daka is forced to remember horrible memories of her past when she is taken hostage by Kira, after the Agency is infiltrated by the villain and most members are defeated. Daka grabs on to her little remaining hope, when S appears after coming from the future.

After realizing that Daka has been taken hostage, S defeats Kira in battle. Once she is defeated, it is revealed to the girls that, through the destiny of time travel, all of those born in the future after Kira has taken over will be erased from existence.

All members of the Agency who came from the future disappear at this point, leaving the girls depressed. They head back to their homes, but it is later revealed that the Agency's purpose is changed, and S becomes new leader of the Agency, three years later in Violet War.


As Reverse Quantum Curse is a 2D game, the player may only move left and right. Occasionally, in places such as The Agency and London Town Square, the area is three-dimensional, and you may go in any direction. The touch screen (or cursor) is used a lot in the game to uncover hidden objects, select items, and talk to NPCs. You may also press A (3DS) or Z (Steam) to select objects.

The player has a bar of health at the top of the screen. It defaults to having three sections. Each time you are hurt, a section is erased. You may gain more of these sections through Health Upgrades. These can be obtained by solving mysteries.

Similar to in many RPGs, you gain Experience Points after defeating enemies and solving mysteries. Every time you level up, you are allowed to solve higher-level mysteries. Unlike in RPGs, your health and attack do not raise after you level up. You cannot progress in the game unless you level up often, however.

The player always plays as S in the game, and Daka is usually walking around with you. You may attack through kicking and punching, although that is not used often. Jumping to reach higher objects or locations is used a lot throughout the game. Daka can occasionally pick up S to help her to jump higher. You may also press B (3DS) or X (Steam) to run faster through stages. If you press B and Y (3DS) or X and C (Steam) together, S and Daka will hold hands and run faster than before.

Nintendo eShop/Steam Description

Reverse Quantum Curse

Strange happenings are breaking out across Victorian London, all centred around the rise of the killer, Kira! S, an orphan, is chosen by The Agency to solve these mysteries. Play as S and Daka and investigate many mysterious happenings across the city, and work to save the kingdom from being overthrown by Kira!

Quantum Curse Rewritten

A high-definition remake of the original Reverse Quantum Curse with many added features! Play as S and Daka, once again, and investigate many NEW mysteries across London, and thwart the killer, Kira! There's a secret after you finish your quest...


Name Description
S S is a sweet girl, but her parents were killed when she was young. She joined the Agency for hope of becoming stronger, and being able to help people from having the same type of accident happening to them. She later goes on a large journey for the sake of the entire country of England.
Daka Daka is occasionally rude towards others. She comes from a household in which her parents are always arguing, and her sister died at the age of 3. She seems to be depressed a lot, but enjoys being around S. She goes on a quest to protect her friends, but is forced through more painful experiences.
Boss A. Boss A. is the leader of the Agency. He came from the future to save the country of England from Kira, but is met with many hard tasks on his way. After revealing the secret of the Agency to S and Daka, his adventure becomes much more complicated, and the Agency and XGen forces battle fiercely.
Kira Kira is a villain with the natural power to time travel. She plans to take over England in the year 1830, before anyone can stop her. She starts the agency of XGen to aid her on her seize of the country. However, an agency from the future that she devastated arrives and stops her.


Name Description
Heart Heals one of your sections of health.
Potion Heals half of your health.
Super Potion Heals all of your health.
Power Potion Makes your punches and kicks momentarily stronger.
Diary Keeps your daily efforts written down. You also save from here.
Health Upgrade Adds a section to your health permanently.
Power Upgrade Makes your punches and kicks permanently stronger.
Pounds (£) Allows you to buy items from shops.


  • London Town Square
  • The Agency
  • Short River
  • The Inn
  • Home
  • Daka's House
  • London Forest
  • Violet's House
  • Boss's Quarters
  • Batél Bridge
  • XGen
  • London, 3005 A.D.
  • The Agency, 3005 A.D.
  • Agency Airship
  • XGen Tower
  • New London

Quantum Curse Rewritten

Main Article: Quantum Curse Rewritten

Quantum Curse Rewritten is a remake of the original Reverse Quantum Curse, that was released on 22 November 2012 for the Wii U and on 22 February 2014 for Steam. It was mainly released to recapture the gameplay experience of Reverse Quantum Curse in high definition.

Special deals in America and Canada sell Quantum Curse Rewritten and Violet War together for $70, including retail and Nintendo's eShop. Steam will sell the two together for $50.

Despite it being mainly for being the playing of RCQ in HD, there are quite a few extra features in this remake.

  • After the game is beaten, rather than making the player go to his/her last save point, a new game is created in place of the file, where the player may play the entire game as S in her violet pajamas.
  • There are twelve new mysteries.
  • Similar to in Violet War, when you level up, your max. HP and Attack Power are risen. Instead of gaining power or health upgrades after solving mysteries, you will gain special items or money alone.
  • There are two new optional bosses that may be accessed from XGen. One of them is Nero, while the other is a robotic Kirana.
  • An extra cutscene is unlocked if the player solves every mystery.

Investigator S: Quantum Shadows

Quantum Shadows is an upcoming remake of Reverse Quantum Curse for the Throwback Player. The game is completely identical to the 3DS game, though Quantum Shadows uses Gameboy Advance styled graphics, and costs only $4.99. The game will be a launch title for the system.


  • Reverse Quantum Curse and Icebound Katrina: Northern Downfall were co-released, and the two are very similar in many ways.
  • The title of the game refers to the curse of reverse time travel. This is shown when the members of the Agency from the future are forced into vanishing after the past is saved and the future they come from is erased from existence.



  • Main Theme:
    S Main Theme
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