The Saddest of All Keys is a case featured in Criminal Case as the third case of The Conspiracy (Season 5) and the two-hundred thirty-fourth case overall. It takes place in the Fairview district of Grimsborough.
Chief Parker told Jones and the player to secure the Grimsborough Arena for the reunion concert of The Henge, an English rock band. In the arena, they found the band's lead vocalist, Ian Devine, bleeding out from every orifice in his head.
Mid-investigation, conspiracy theorist Izzy Ramsey loudly proclaimed outside the arena that the real Ian had actually died in 1969. Later, Boris Chiswick's Irish Wolfhound scared the team before Boris came and took him away. The team then found enough evidence to arrest the victim's manager, Kevin St Kevin, for the murder.
Upon admitting to the murder, Kevin said that The Henge's reunion tour was failing financially because there was not much hype around them anymore. Knowing that a band's record sales go up when one of its members dies, Kevin used a sound-emitting device to play an infrasound frequency that liquefied Ian's brain tissues. Judge Powell sentenced Kevin to 25 years in jail for the murder.
After the trial, Gloria and the player went to Izzy, who was proclaiming another conspiracy theory. She claimed that people were dying for similar reasons all around Grimsborough, but she had lost the USB key containing all of her proof. Gloria and the player found the key outside the arena, which (per Cathy) contained proof that ten people had died of sudden heart failure and had high levels of amlodipine in their blood upon their deaths, much like David O'Connell. Furthermore, Tank's wife Emma was one of the listed casualties, so Gloria and the player went to talk to him.
When they were talking to him, Tank said that Emma kept track of everything she ate. He directed the team to the arena to find his briefcase containing her food diary. Gloria and the player found the diary, which (per Martine) proved that Emma drank Rocket Cow on the day of her death, much like David had. Martine then contacted the hospitals to learn more about the stomach contents of the other nine casualties.
Meanwhile, Cathy and the player took Alex to the airport so he could meet Boris, his musical idol. After all the events, Martine was able to confirm that all of the ten people who died of heart failure had drunk Rocket Cow on the day of their deaths. With a shipment of amlodipine going missing from the zoo, Martine concluded that someone had orchestrated all eleven known deaths. After the team reported their findings to her, Chief Parker told everyone to stay alert for the serial killer.
- Ian Devine (found bleeding out of his eyes and ears)
- Sound Frequency
- Kevin St Kevin
- The killer drinks Gold Stag whiskey.
- The killer is claustrophobic.
- The killer has an Irish Wolfhound.
- The killer has a tattoo.
- The killer is male.
- Investigate Rock Stage. (Clues: Damaged Badge, Concert Gear Box, Victim's Body)
- Examine Damaged Badge. (New Suspect: Kevin St Kevin)
- Ask Kevin St Kevin why his badge was on the crime scene. (Prerequisite: Kevin St Kevin decoded; New Crime Scene Unlocked: Music Store; Victim identified: Ian Devine)
- Investigate Music Store. (Prerequisite: Kevin interrogated; Clues: Chunks of Wood, Faded Photo)
- Examine Chunks of Wood. (Result: Signature Bass; New Suspect: Boris Chiswick)
- Question Boris Chiswick about his broken bass guitar. (Prerequisite: Signature Bass restored)
- Examine Faded Photo. (Result: Photo [Unknown Man])
- Examine Unknown Man. (New Suspect: Tank)
- Ask Tank about his relationship with the victim. (Prerequisite: Tank identified)
- Examine Concert Gear Box. (Result: Bloody Blister Pack)
- Analyze Bloody Blister Pack. (03:00:00; Attribute: The killer is claustrophobic)
- Autopsy Victim's Body. (18:00:00; Murder Weapon registered: Sound Frequency; Attribute: The killer drinks Gold Stag whiskey)
- Go to Chapter 2. (1 star)
- Interrogate Izzy Ramsey regarding her wild claims about the victim. (Available after unlocking Chapter 2; New Crime Scene Unlocked: Concert Venue)
- Investigate Concert Venue. (Prerequisite: Izzy interrogated; Clues: Box for Victim, CD)
- Examine Box for Victim. (Result: Pink Handcuffs; New Suspect: Rose Sweet)
- Question Rose Sweet about her relationship with the victim. (Prerequisite: Pink Handcuffs found; Profile updated: Rose drinks Gold Stag whiskey)
- Examine CD. (Result: Hair)
- Analyze Hair. (12:00:00; Attribute: The killer has an Irish Wolfhound; New Crime Scene Unlocked: Shop Floor)
- Investigate Shop Floor. (Prerequisite: Hair analyzed; Clues: Defaced Poster, Torn Plush Toy)
- Examine Defaced Poster. (Result: Oily Substance)
- Examine Oily Substance. (Result: Bass Guitar Oil)
- Ask Boris about the defaced poster of the victim. (Prerequisite: Bass Guitar Oil identified under microscope; Profile updated: Boris drinks Gold Stag whiskey)
- Examine Torn Plush Toy. (Result: Teddy Bear [Teddy Bear Note])
- Analyze Teddy Bear Note. (12:00:00)
- Question Tank about why he destroyed a gift from the victim. (Prerequisite: Teddy Bear Note analyzed; Profile updated: Tank drinks Gold Stag whiskey, is claustrophobic and has an Irish Wolfhound)
- Go to Chapter 3. (1 star)
- Profiles updated: Boris has an Irish Wolfhound, Kevin has an Irish Wolfhound
- Investigate Food Truck. (Available after unlocking Chapter 3; Clues: Trash Bag, Faded Magazine, Laptop)
- Examine Trash Bag. (Result: Toothbrush)
- Analyze Toothbrush. (09:00:00)
- Tell Izzy she was the victim's daughter. (Prerequisite: Toothbrush analyzed; Profile updated: Izzy is claustrophobic)
- Examine Faded Magazine. (Result: Magazine Cover)
- Ask Kevin about the victim quitting the tour. (Prerequisite: Magazine Cover unraveled; Profile updated: Kevin drinks Gold Stag whiskey and is claustrophobic)
- Examine Laptop. (Result: Video File; Profile updated: Rose is claustrophobic)
- Question Rose about her fight with the victim. (Prerequisite: Video File deciphered; Profile updated: Rose has an Irish Wolfhound)
- Investigate Gear Crates. (All tasks before must be done first; Clues: Broken Device, Bloody Headphones)
- Examine Broken Device. (Result: Strange Device)
- Analyze Strange Device. (15:00:00; Attribute: The killer has a tattoo)
- Examine Bloody Headphones. (Result: Blood)
- Analyze Blood. (09:00:00; Attribute: The killer is male)
- Take care of the killer now!
- Go to Old Friends, New Beginnings (3/6). (No stars)
Old Friends, New Beginnings (3/6)
- Talk to Cathy about her request. (Available after unlocking Old Friends, New Beginnings; Reward: 20,000 Coins)
- Investigate Music Store. (Prerequisite: Cathy interrogated; Clue: Faded Passport)
- Examine Faded Passport. (Result: Boris' Passport)
- Analyze Boris' Passport. (06:00:00)
- Take Alex to meet Boris Chiswick. (Prerequisite: Boris' Passport analyzed; Reward: Rock Haircut)
- Confront Izzy about her latest theory. (Available after unlocking Old Friends, New Beginnings)
- Investigate Concert Venue. (Prerequisite: Izzy interrogated; Clue: Display Stand)
- Examine Display Stand. (Result: USB Key)
- Analyze USB Key. (09:00:00)
- Ask Tank about his wife's symptoms. (Prerequisite: USB Key analyzed; Reward: Burger)
- Investigate Gear Crates. (Prerequisite: Tank interrogated; Clue: Briefcase)
- Examine Briefcase. (Result: Food Diary)
- Analyze Food Diary. (06:00:00)
- Move on to a new crime! (1 star)
- Long Live Rock, a magazine that can be seen in the "Food Truck" crime scene, is a parody of Rolling Stone.
- In the "Rock Stage" crime scene, a crystalline skull can be seen, most likely a reference of the crystal skull featured in Indiana Jones and the Kingdom of the Crystal Skull, a movie from the Indiana Jones franchise.
- A photo of Billy Gibbons can be seen on a magazine in the "Gears Crate" crime scene.
- In Old Friends, New Beginnings, Jimi Hendrix is mentioned.
- The cover photo of the third chapter is a reference to the "up to eleven" scene in the movie This Is Spinal Tap.
- The stage appearing in the "Rock Stage" crime scene is a reference to the stage of the 2017 edition of the Eurovision Song Contest.