PHOENIX WRIGHT / GYAKUTEN SAIBAN
The first case of the game presents defense attorney Phoenix Wright at his first trial under Mia Fey's watchful eye, successfully defending his childhood friend Larry Butz for murder. However, in the game's second case, Mia is murdered for being aware of corporate blackmail, and her younger sister Maya Fey is charged with the crime because her name was found on a piece of evidence. While defending her, Phoenix is reintroduced to another childhood friend, Miles Edgeworth, who is the prosecutor for Maya's case and has established himself as a "genius" for the prosecution system. Maya is found not guilty of the crime, and becomes Phoenix's assistant in further cases, offering her channeling ability as a "Spirit Medium" of Kurain village to bring the spirit of Mia to help at critical times. Phoenix and Miles find that while they have their friendship from their youth, they continue to face off against each other in the courtroom.
In one case, Miles is charged with murder, and Phoenix steps up to defend him. It is discovered that Miles was set up by his old mentor, Manfred von Karma. Several years earlier, Manfred shot and killed Miles' father, a defense attorney, after he ruined Manfred's perfect record, but led Miles to believe he shot his own father. Phoenix is able to expose Manfred's cover-up and achieve a "not guilty" verdict for Miles. After the case, Miles thinks about taking time off from his position to consider the events, while Maya announces she is going back to her home in Kurain Village to train.
The fifth case, added for the Nintendo DS, iOS, and Wii versions, has Ema Skye begging Wright for help to defend her older sister Lana, who is on trial for murder, compounded by a second murder of the same apparent victim in a different building at the same time. Using Ema's scientific help to establish evidence and the surprising prosecution help of Miles during the trial, Phoenix is able to learn that Lana Skye was blackmailed by the Chief of Police Damon Gant into covering for a murder she thought that Ema had committed several years before when in actuality Gant himself had committed it and pinned the blame on Ema. Though Lana is cleared of murder charges, she willingly goes to jail for being an accomplice; Ema says her goodbyes as she heads to Europe to study forensic science.
ACE ATTORNEY INVESTIGATIONS: MILES EDGEWORTH / GYAKUTEN KENJI
Similar to previous Ace Attorney games, there are five cases in the game, and to unlock a new case, the previous case needs to be solved. Chronologically, the game appears to take place after Trials and Tribulations and before Apollo Justice. The five cases are presented out of chronological order in the game, though each describe a series of common events connected to an international smuggling ring and the Great Thief Yatagarasu that seeks to expose the smuggling ring by "stealing the truth" and revealing the evidence to the public.
The fourth case, "Turnabout Reminiscence", describes most of the backstory for the rest of the game. Ten years prior to the game's present, during what became known as the "KG-8 Incident", the Secretariat of the Cohdopian Embassy, Manny Coachen, was accused of the murder of Cece Yew, a witness to the connection of the smuggling ring to the embassy. Lead prosecutor Byrne Faraday, working with his partner Detective Tyrell Badd, attempted to convict Manny Coachen. However, key evidence was stolen from them by the ring and Coachen went free. Calisto Yew, posing as Cece's sister and a defense attorney, accosted Faraday and Badd after the trial. Realizing that the justice system was powerless to convict those above the law, the three formed the Yatagarasu. Three years later, a similar murder at the Cohdopian Embassy occurred; the suspect Mack Rell claimed he was told to perform the murder by Faraday, the prosecutor of the trial, pointing him out as Yatagarasu. A recess was held to replace Faraday with Edgeworth (in his first appearance as prosecutor as well as his first meeting with Dick Gumshoe), but before recess was completed, both Faraday and the suspect were found murdered. Edgeworth discovers that Calisto Yew murdered Faraday with Rell's help, then killed Rell and altered the crime scene to make it seem that they killed each other. When they confront Yew she pulls a gun on them and claims to be the Yatagarasu (excluding mention of her two partners) as well as a minion of the smuggling ring. Faraday's young daughter, Kay, is comforted over her father's death by Edgeworth, Gumshoe, and Badd; she believes that her father was the true Yatagarasu, and vows to catch the fake Yatagarasu some day.
In the game's present, Edgeworth becomes involved with a branch operation of the smuggling ring on his return trip aboard an airliner ("Turnabout Airlines", the game's 2nd case). An Interpol agent investigating the smuggling is murdered during the flight, with first Edgeworth, then a flight attendant, Rhoda Teneiro, becoming the main suspects. Edgeworth meets with his fellow prosecutor, Franziska von Karma, who explains she is working with Interpol to expose the smuggling ring. Edgeworth discovers the real murderer to be another flight attendant, Cammy Meele, who is also working with the smuggling ring. After closing that case, Edgeworth is called by Ernest Amano, head of a powerful business group, whose son Lance has been kidnapped and held at a local amusement park ("The Kidnapped Turnabout", the 3rd case). Edgeworth is kidnapped himself when attempting to exchange the ransom money, but is helped free by Kay Faraday, now calling herself the true Yatagarasu. The situation is further complicated by the discovery of the murder of Oliver Deacon, who is identified as one of the kidnappers by a released Lance. As Edgeworth seeks to solve the mystery, he is introduced to Interpol agents Shi-Long Lang and his assistant Shih-Na, who believe the Amano Group is involved with the smuggling ring, and are seeking to end it, after the ring's counterfeit money operation ruined the economy of their home country, Zheng Fa. Edgeworth reveals the kidnapping as a ploy by Lance to get money from his father, and had murdered Deacon when he decided to back out of the plan. However, enough evidence is revealed for Lang to bring Ernest Amano in for questioning. This is revealed to be Lang's plan all along, as he believes Amano is involved with the smuggling ring and needed an excuse to arrest him. Upon returning to his office building, Edgeworth finds yet another murder has occurred in his own office ("Turnabout Visitor" , the 1st case). Edgeworth deduces that a corrupt prosecutor, Jacques Portsman, was working for the smuggling ring and was seeking to steal evidence from the KG-8 Incident in Edgeworth's office, and had killed a detective who was getting too close.
The final case of the game, "Turnabout Ablaze", takes places a few days later at the former embassy of Cohdopia; in years prior, civil tension in the country of Cohdopia forced the country to split in two, into the nations of Allebahst and Babahl, sharing the same embassy building. On a night that the two nations were secretly planning on announcing their reunification as a single country at the embassy, the fake Yatagarasu appeared, along with a fire on the Babahl half of the embassy and a double murder in the respective offices of Allebahst and Babahl embassies; one of the victims is found to be Manny Coachen, the Secretariat for Babahl and still a prime suspect in the smuggling ring. Shih-Na is revealed to be Calisto Yew, undercover with Interpol. She insists that she did not murder Coachen and is later to be revealed to only be an accessory to the crime. As she is taken away, she reveals she is not Cece's sister; Calisto Yew is another one of her aliases as an agent from the smuggling ring, and her membership in Yatagarasu was ordered by the Ring's leader. Further investigation by Edgeworth, using the illegal evidence obtained by Badd years ago, eventually pins Allebahst's (and former Cohdopia's) Ambassador Quercus Alba as the ringmaster of the smuggling ring from the start, planning and committing the murders and covering the tracks of the smuggling ring, including the introduction of counterfeit money into Zheng Fa. Alba, Amano, and others are convicted of their crimes, while Edgeworth and his newfound friends recommit to their vows to defend the truth.