Criminal Case: Mysteries of the Past is the fourth game of the Criminal Case series, released in 2016. It is set in the Victorian era.
Following SOMBRA's defeat, Armand Dupont gives his Bureau colleagues the journal of his great-grandfather Charles, detailing the adventures he had in the city of Concordia, as a member of the Flying Squad, with a detective that looks just like the player. The Flying Squad deal with the rise of gang warfare and the corruption plaguing the police force. The story takes place in the 19th Century around ten districts - New Haven, Elysium Hills, Century Mile, Sinner's End, Coyote Gorge, Crimson Banks, Wolf Street, Grim Chapel, Ivory Hill, and Capitol Peak.
Tropes:
- Advertised Extra: One wonders why Lady Highmore is on the preview images for the arc, as she appears as a suspect in two cases in Elysium Fields and made minor appearances afterwards. This is especially unusual since she's occupying the place usually taken by the chief of police of the season.
- Alice Allusion: One of the suspects in Doctor, Interrupted is Alice Riddel, a young girl who carries around a white rabbit, sees delusions of fantastic creatures, and often invites the Player to have a tea party with her.
- Bedlam House: The second half of the Grim Chapel district focuses on investigating Gryphon Sanctuary, a mental asylum where lobotomies and electroshock therapy are common and completely sane people are being hospitalized by the corrupt Rochester family.
- Big, Screwed-Up Family: The Rochester family, a prominent and corrupt family in Concordia, has witnessed infighting within. There are few White Sheep among them, such as Leopold, Rockley, Bernadine, and Viola.
- Bluffing the Murderer: In Breaking the Glass Ceiling, Madeline got the killer to confess by saying that the note they sent to the victim revealed their fear of heights. The accused sealed their fate when they denied writing such a thing on said note.
- Bubblegum Popping: Lab Chief Viola Pemberton, will blow and pop gum on occasion in the lab.
- Call-Forward: In That Sinking Feeling, we meet several minor characters who mention that they are going to board the Gigantic ship—which, as we already know from the Pacific Bay Arc, is going to sink.
- Deliberate Values Dissonance: Despite Concordia being mostly a Politically Correct History, the game does make several attempts to show a different set cultural values prevalent in the late Victorian Era, such as mentioning the taboos of living together before marriage, bearing a child out of wedlock, etc.
- Dirty Cop: The Concordian Police Department is filled with some of these, which leads to the inception of the Concordian Flying Squad as the Internal Affairs to investigate them.
- Enemy Mine: Bounty Hunter Catastrophe Joan has a bitter history with Rose, who is formerly a bounty hunter herself. But the two made amends in order to bring down Vittorio Cappecchi and his goons when the latter challenged the Flying Squad to a shoot-out.
- Identical Grandson: The detective described by Charlie Dupont's journals looks and acts almost exactly the same as the player, and is likely their ancestor. This is Subverted at the end of season 8, where a descendent of Charlie and Maddie is talking with Amy Young, and reveals that the player character actually knew Charlie. It's not an Identical Grandson, it's Time Travel — just like in season 6.
- Internal Affairs: The Myth Arc set-up for Season 4. Rumours of the possible corruption within the Concordian Police Force have led to the inception of the Flying Squad.
- In Vino Veritas: The reason for Anna Jewell's death in Get off Your High Horse. Anna knew "Princess Eliza Rheinberg of Splichtenstein" had really been Eliza Fairfax, a poor flower girl from when both were childhood friends. Later in life Eliza took on her Princess Persona. Anna recognized Eliza at a soiree, however, and Anna began talking more when she got drunk. Afraid Anna would expose her Eliza initially tried to talk to Anna in the stables, but her temper got the better of her, causing her to bash her one-time childhood friend's head in with a stirrup.
- Jack the Ripoff: The Scarlet Slayer has several similarities with the infamous Jack the Ripper. Both killers were active during the late Victorian era, primarily targeted female prostitutes, and killed their victims in areas of poverty and corruption.
- Karma Houdini: Mr. Alastor spent the entire Elysium Fields arc setting up proxy-murders in order to impress Giuletta Capecchi. After his scheme is discovered, he... gets away with all of it because he technically didn't kill anyone and couldn't be convicted by law.
- Karma Houdini Warranty: "Mr. Alastor" eventually ends up being the victim in Tipping the Scales, as his father had tried to double-cross Archie's murderer by not intending to honor promises to the murderer made in return for supporting turning Concordia into a family city-state.
- Loony Fan: The killer of The New Truth! killed Judge Takakura for criticizing Justin Lawson, whom she idolized.
- Mayor Pain: Mayor Lawson quickly turns into a ruthless dictator in his quest to rid Concordia of crime, forming a secret police answerable only to him, mandating the death penalty for any crime regardless of its severity, imposing censorship on the press, and ordering the arrest of anyone who opposes his policies.
- Nested Story: The plot of Season 4 is derived from the memoirs of Charles Dupont, the great-grandfather of Armand Dupont.
- Plot Archaeology: The Rochester family's corruption and evasion of justice are brought up during Elysium Fields, the game's second district, as the Arc Villain ends up being a Karma Houdini for his actions due to how powerful and influential his family is, but nothing is really resolved and the Rochesters mostly disappear from the story when you leave Elysium Fields. Twenty-four cases later, though, you reach Wolf Street, the game's seventh district and where the Rochesters officially become the main focus of the story for the next three arcs as you attempt to dismantle their corruption machine and stronghold over the city.
- Politically Correct History: Despite being set in the late 19th Century - early 20th Century in the USA, the cast of the fourth season is somehow more diverse than most of the other seasons, which are set in modern times. There is a distinct lack of prejudice against people of colour and/or different sexuality. The Concordian Flying Squad alone features 2 black characters (Isaac and Violet), 1 Asian (Rose), a lesbian (Evie), and later joined by 1 Latino (Diego), and that's not counting the city officials, which features a black mayor, an Asian deputy mayor and an Asian judge. By contrast, the Grimsborough PD initially has two non-whites—Nathan (Indian) and Ramirez (Hispanic); the Pacific Bay team has 3—Chief Marquez (Hispanic), Yann (black) and Hannah (Asian, and also a lesbian); The Bureau has 2 non-whites at first—Angela (Asian) and Carmen (Hispanic), although they are later joined by Jonah Karam (black) and Michelle (Ambiguously Brown).
- Self-Offense: The violent gang war taking place in Crimson Bank eventually caused one street kid to accidentally kill another when the former thought he was being attacked by a gang member.
- "Shaggy Dog" Story: The conclusion of the Ivory Hill arc ends with this. The Flying Squad had spent the entire 6 cases trying to stop the Rochesters from rising to power and enacting a bill that would end free press. They manage to dismantle the family's power and influence over Concordia, only for the bill to be enacted anyway when Justin Lawson becomes the Mayor.
- Shoot Your Mate: Diego del Lobo is forced to kill his former teammate Charlie while he's trying to infiltrate into Justin Lawson's inner circle to take him down. Lawson, who has been on a crackdown on the Concordian Flying Squad, orders Diego, who is living under the alias of Eddie Lebold to execute Charlie when they are meeting up to discuss their plans to prove his loyalty to him.
- Shout-Out: In The Victim's Vault scene of "Case 37: Death Comes to Lunch", there is a satirical version of Girl with a Pearl Earring.
- Steampunk: What the main aesthetics of this season are, mechanical arms, airships, top hats with goggles, an entire district dedicated to invention, the works.
- Taking the Heat: Leopold Rochester allows himself to be arrested for endorsing investment bonds in a company that doesn't exist even though he's not actually involved in the scam. Larry was the one behind the fake company and Leopold endorsed it, believing that his wayward son had finally made use of his life. When the player revealed the truth, Leopold took the fall in order to protect Larry from being arrested.
- Under Strange Management: The heroes, who are essentialy police Internal Affairs end up running a telephone company when they discover that it's a scam and try to salvage it so that all the locals who invested in it won't lose their money.
- Whole-Plot Reference: The final arc takes heavy inspiration from Les Misérables. Concordia has become a chaotic place ruled by a tyrant, while a group of La Résistance attempts to dismantle the autocratic dictator. It features many expy to the novel's characters, such as: an impoverished young woman (Adelia Baldwin) who has a child out of wedlock and is forced into hard labour and prostitution to support her child like Fantine, a greedy and abusive woman surnamed Thenard who basically took Adelia's child hostage and forces to prostitute herself, a police officer employed in the new regime to arrest the hero named Jaubert, and an outspoken resistance fighter named Enzo Jonas.
