Maddie: Understanding that Sinner's End is Irish territory, the Italians could be trying to undermine the Irish stronghold in this part of town. If this is true, there won't be much stopping the two factions from plunging this city into a bloody gang war!
After learning in the previous case that a Serial Killer named the Scarlet Slayer was targeting the prostitutes of Sinner's End, Maddie and the player decide to take a look at the local park where the brothel ladies tend to work. There, both officers don't stumble onto a prostitute, but rather the body of Italian gangster Joseph Dante with a stab wound in his back, signs of poisoning, and a message claiming him to be the Scarlet Slayer.
Tropes:
- All for Nothing: Not only did Madame Xiang lose her freedom by killing Joseph, it turns out she didn't even kill the Scarlet Slayer, as another prostitute's body is found after her trial.
- Arranged Marriage: Maddie's mother attempts to engage her daughter with a sexagenarian doctor during the Additional Investigation, which terrifies Maddie and is enough to make her implore Charlie pretend to be her fiancé.
- Back Stab: The victim was stabbed in the back with a knife, although what truly killed him was the poisonous belladonna the blade was laced with.
- Big Brother Instinct: Tony, the victim's brother, warned him about visiting Sinner's End because of the district being Irish territory, wishing to protect him from harm and the rival gang.
- Blame Game: As expected, the Italian Tony keeps blaming the Irish of killing his brother, while the Irish Eamon blames the Italians for killing the prostitutes working under them.
- Call-Back: Gladys Perrin and Madam Xiang reappear as suspects, while Lady Highmore reappears during the Additional Investigation.
- Calling Card: The Scarlet Slayer has one in the form of dove feathers they leave in their victims' bodies, which as Katherine points out, might be a reference to prostitutes being nicknamed "soiled doves".
- Catching Some Z's: This happens to Evie when she falls asleep after accidentally ingesting an insomnia elixir mistaking it for honey.
- Continuity Nod: Just like she said in Case 11, Maddie's mom attempts to engage her with someone against her own wishes
- Couldn't Find a Pen: Caitlin, the Scarlet Slayer's latest victim, left a handkerchief scribbled with her own blood calling for help after the Scarlet Slayer took her to the public restrooms to finish her off.
- Covered in Kisses: Constable Ramirez is left in this state after a group of prostitutes "distract" him with multiple kisses, since they don't want the culprit to be found because, as far as they know, the victim was the Scarlet Slayer and therefore his murderer is a hero.
- Curse Cut Short: Maddie does this to herself while reading the instructions for a machine used to treat erectile dysfunction.Maddie: According to the instructions, the male patient plugs the metal prongs into the box and then gives an electrical shock to their...Oh... my...
- I Did What I Had to Do:
- Gladys tells you that she had to become a prostitute again because her mother is sick and being a barber shop assistant doesn't pay enough.
- During her trial, Madam Xiang excuses her actions by claiming that, since the police wasn't doing anything to stop the Scarlet Slayer, she had to take matters in her own hands and kill the person she believed the Scarlet Slayer was.
- Dirty Coward: When you interrupt the fight between Tony and Eamon, Tony runs away while Eamon decides to stay and allows himself to be interrogated, calling Tony a coward in the process.
- Disgusting Public Toilet: One of the crime scenes is one, which also happens to be where the Scarlet Slayer leaves their latest victim.
- Distracted by the Sexy: Invoked by the prostitutes trying to derail the investigation by distracting Constable Ramirez with kisses, since they don't want the supposed Scarlet Slayer's killer to be captured.
- Doesn't Trust Those Guys: Tony refers to the Irish this way.Maddie: They? Who's they? Do you know who killed Mr Dante?Tony: Naturalmente... It was those filthy Irish, who else?
- Fake Relationship: Maddie and Charlie pretend to be engaged during the Additional Investigation to deter Maddie's mom from engaging her with a sexagenarian doctor.
- Faux Horrific: For Constable Ramirez, being "attacked" by multiple prostitutes with a barrage of kisses is enough to make him call the Flying Squad asking for help, claiming it to be an emergency.
- Gangbangers: Two of them are introduced this case as suspects: Antonio Dante (also known as Tony "The Scorpion") for the Italians and Eamon Gilligan for the Irish. The victim was also one of them, pertaining to the Italian faction.
- Gutted Like a Fish: This is how the Scarlet Slayer kills their victims: by disemboweling them with a knife.
- Implied Death Threat: Mad Dog sent a coffin to Madam Xiang with a message telling her to remember what her loyalties are since he found out she was allowing Italians to sleep with her girls, which she does because, in her own words, business are business.
- In the Back: The poisoning that killed Joseph occured when he was stabbed in the back with a knife coated in belladonna.
- The Insomniac: One of the killer's traits is that they're suffering from insomnia since the murder weapon was covered in their insomnia medication.
- The Loins Sleep Tonight: The victim apparently had erectile dysfunction, since you find a machine Theodosia Hayhurst, her apothecary, prescribed to him to supposedly cure it.
- Misplaced Retribution: Madam Xiang murdered Joseph because her clandestine investigation led her to conclude he was the Scarlet Slayer and, since the police wasn't doing anything, she took the matters in her own hands. Unfortunately, you discover after the case is solved that Joseph not only wasn't the Scarlet Slayer, but they have killed another prostitute in the meantime.
- Not Good with Rejection: Joseph was in love with Gladys, mistaking their time together for a relationship while she was only doing her job. And according to Gladys, he got pretty violent with her once she rejected him, giving her a motive to kill him.
- Number Two: Eamon claims himself to be Mad Dog's leading man, putting him in this category. Apparently, he's in charge of keeping Sinner's End clean of Italian intervention.
- Parents in Distress: Gladys' reason for going back to being a prostitute is because her mother has fallen sick and being a barber shop assisant doesn't pay enough.
- Poisoned Weapons: The victim was killed by being stabbed with a knife laced with belladonna, a poisonous plant.
- Seeking the Missing, Finding the Dead: The search for a missing Caitlin during the Additional Investigation inevitably leads to you finding her body, dead after being murdered by the Scarlet Slayer.
- Ship Tease: A big one between Maddie and Charlie, as Maddie requests Charlie's assistance by pretending to be her fiance and gives him a kiss in the cheek when he complies, making both of them blush.
- Significant Wardrobe Shift: Gladys shifts to a more "appealing" outfit due to becoming a prostitute once again.Maddie: Wow, Gladys, you've certainly changed! Quite the switch from the barber shop clothing...
- Sympathetic Murderer: Madam Xiang was just a desperate woman who wanted to keep her girls safe from a deranged Serial Killer because the police wasn't helping, and said desperation led her to assume the victim was the Scarlet Slayer. When you inform her in prison that another prostitute has died and therefore Joseph wasn't the Scarlet Slayer, she's understandably heartbroken.
- There Are No Coincidences: Madam Xiang came to the conclusion that Joseph was the Scarlet Slayer because she kept tabs on him and she saw a pattern where all of her girls had slept with him prior to being murdered, which she found hard to be a coincidence. Unfortunately for her, she was dead wrong and it really was a coincidence.
- There Is No Kill Like Overkill: Going with the case's title, the victim was not only stabbed in the back, but also poisoned with belladonna at the same time.Maddie: So our victim was both stabbed and poisoned to death? That's a bit overkill...
- Vigilante Woman: Madam Xiang decided to take justice on her own hands by killing the person most likely to be the Scarlet Slayer. Too bad her deduction was mistaken.
- What the Hell, Hero?: Madam Xiang has this opinion regarding the Concordian police and the Flying Squad due to them failing to catch the Scarlet Slayer.Madam Xiang: Three girls have gone missing! Three! They disappeared into thin air... They're probably dead! But you don't do anything!
