- Box One was used prior to the end of Season Two. It contained forty-six blood slides when it was stolen.
- Box Two was used from Season Three to Season Seven. It contained forty-three blood slides when it was destroyed.
Dexter didn't always collect slides as trophies. Rather, he spent his early years simply killing. The first of his blood slides was taken from Alex Timmons, a sniper. Thereafter, he continued to collect them whenever possible.
Collection of Slides
During a planned kill, Dexter usually collected a blood slide as a trophy. To do this, he would slice a victim’s cheek with a surgical scalpel and place a drop of blood between two microscope slides. Dexter enjoyed reminiscing over his collection of blood trophies. He would open the box and run his fingers gently across the top of the slides as the glass slightly clattered. At times, he referred to the slides as “friends."
Storage of Slides
The blood slide box was kept hidden within a compartment inside Dexter's thru-the-wall air conditioner. When someone went near the air conditioner, Dexter became apprehensive. The unit was fully functional, so there was little reason for visitors to tamper with it.
Each box had storage for 50 slides, however, Dexter never managed to fill either one. Made with a polished oak finish, the boxes had white plastic holders for each slide, and were numbered down the sides. It's unknown if Dexter kept any identifying information elsewhere in the boxes to discern one victim from another.
First Slide Box
The viewers were first shown this box in the opening episode, when Dexter inserted Mike Donovan's blood slide into it next to his previous victims.
The existence of this box was known to Brian Moser, Dexter's older, biological brother. As part of a game, Brian took the slide that belonged to Valerie Castillo and scraped a "smiley face" in its blood droplet.
Following Dexter's murder of Jorge and Valerie Castillo, her body resurfaced as part of Brian's game. In fear that he could be identified by a child witness, Dexter nearly dumped his box overboard, in order to get rid of evidence against him. But as Dexter looked through his slides one last time remembering his kills, including those of Alex Timmons, Cindy Landon, and Gene Marshall, he noticed the smile on Valerie's slide. Feeling that this was a friendly message, Dexter decided to keep the box, and later added more slides to it. However, he did not add his brother, saying at the time of the kill that he was "not a trophy."
Sergeant James Doakes became increasingly suspicious of Dexter and stepped up his investigation of him. When he broke into Dexter's apartment in search of evidence linking him to the Ice Truck Killer, he discovered the blood slide box. Doakes was unsure of what the box exactly meant, but was determined to find out. He stole the box, locked it in the trunk of his car, flew to Haiti, and asked an old friend to have the slides analyzed. However, while Doakes was out of the country, the box was found by the FBI after Special Agent Frank Lundy named Doakes as a suspect in the Bay Harbor Butcher Case.
When Dexter arrived home, he realized that the blood slide box was missing and panicked. Feeling that the FBI was closing in, his fears heightened when they knocked on his door and ordered him to to go along with them. Believing that he was finally exposed as a serial killer, Dexter quietly accompanied the FBI to the Miami Metro Police Department. As he was brought before Frank Lundy and Captain Thomas Matthews, Dexter noticed his blood slide box sitting prominently on a desk. Dexter was told to sit down and put on gloves. Then Matthews blatantly (and somewhat coldly) asked him to explain the box of slides. In one word, Dexter said, "Trophies." Lundy agreed and revealed that the box was found in James Doakes' car and that he was their primary suspect. Dexter tried not to show his relief. Lundy, knowing that Doakes had previously attacked Dexter, assigned a protective detail to Dexter.
To Dexter's surprise, Matthews instructed Dexter to analyze and match the slides. To run the tests, Dexter took the box to his lab where he placed blood scrapings from the slides into multiple tubes. As he did this, he carefully returned each slide to the box. Then he thoroughly wiped the box to remove his own fingerprints. After the tests were completed, the box was closed and returned to evidence. Later, it was shipped off to FBI archives outside of Miami Metro Homicide's jurisdiction. Several years pass before first the box was seen again.
Second Slide Box
Dexter bought the second box in the finale of Season Two. In "Our Father," while Dexter was at a dentist appointment, flashbacks showed him killing Cal Rooney and adding his slide to four others already in the new box (victims that he had killed between seasons). Dexter remarked in monologue that he had met "new people." This new box was stored in the same location as the previous one - inside his air conditioner.
Dexter moved his kill tools and blood slide box into a shed located behind his house with wife, Rita. As in his apartment, the blood slide box was hidden in a compartment inside its air conditioner. It was in this location that Dexter broke Jonathan Farrow's slide after he realized that he had killed the wrong person.
During "My Bad," Dexter decided to disappear and torched the inside of the shipping container where he then kept his kill tools, blood slide box, and files on potential victims. However, he took the blood slide box with him, not yet ready to part with it
Cole Harmon's blood slide was given to Lumen Pierce by Dexter after she witnessed the kill. Although Dexter collected a blood slide from Alex Tilden, he did not keep it since Lumen committed the kill.
In "Smokey and the Bandit," Dexter managed to kill Walter Kenney, a serial killer that he once admired. As he inserted Walter's blood slide into the box, it teetered and crashed to the floor. This caused the slides to fall out and one to break. Dismayed, Dexter said that he had lost order.
The box is shown with the slides placed neatly back inside it. Last season, Dexter had collected a blood slide from Travis Marshall, but he lost it at the crime scene. During the investigation, Captain Maria LaGuerta found the blood slide and it immediately stirred her curiosity. She remembered that during the Bay Harbor Butcher Case, she believed that Doakes wasn't responsible. After some detective work of her own, she gained authorization to obtain (off the books) the original blood slide box. As she endeavored to clear Doakes' name, she found a new suspect - Dexter Morgan.
After Dexter claimed the life of Ray Speltzer in a crematory, he took one last look at the box and ran his fingers across the slides. Then he placed the box on Speltzer's chest, said that it was time to "move on," and pressed a nearby button. This forced Speltzer (and the box) to slide into the flames. Dexter bid farewell to his "friends" as the box burned to ashes along with Speltzer's body.
Box One Victims
- Alex Timmons - "Return to Sender" / "Dexter Early Cuts: Alex Timmons"
- Gene Marshall - "Return to Sender" / "Dexter Early Cuts: Gene Marshall"
- Cindy Landon - "Return to Sender" / "Dexter Early Cuts: Cindy Landon"
- Rick Jensen - "See-Through"
- Jeff Linder - "See-Through"
- Renzo Sandoval - "See-Through"
- Carlos Gutierrez - "See-Through"
- Dylan Maddock - "See-Through"
- Robert Thatcher - "See-Through"
- Marcus White - "See-Through"
- Oscar Sota - "See-Through"
- Joseph Cepeda - "See-Through"
- Chad Carpenter - "That Night, a Forest Grew"
- Shannon Reynolds - "That Night, a Forest Grew"
- Anthony Rodrigo - "Morning Comes"
- Luke Wellens - "There's Something About Harry"
- Andy Jorgen - "There's Something About Harry"
- Rachel Rhodes - "There's Something About Harry"
- Kevin Mott - "There's Something About Harry"
- Jerry Voltic - "There's Something About Harry"
- Sean Dibberman - "There's Something About Harry"
- Berry Cooper - "There's Something About Harry"
- Herbert Washington - "There's Something About Harry"
- Jacob Wilson - "There's Something About Harry"
- George Hoss - "There's Something About Harry"
- Olman Estavez - "There's Something About Harry"
- Rick Cross - "There's Something About Harry"
- Peter Matherson - "There's Something About Harry"
- Alan Elson - "There's Something About Harry"
- Henry Vortman - "There's Something About Harry"
- Larry Costes - "There's Something About Harry"
- Marty Terison - "There's Something About Harry"
- Buck Forester - "There's Something About Harry"
- Alan Matherson - "There's Something About Harry"
- Thomas Hillstat - "There's Something About Harry"
- Larry Mueller - "There's Something About Harry"
- Leandro Noriega - "There's Something About Harry" / "Finding Freebo"
- Walter Munro- "Surprise, Motherfucker!"
- Marcetti - "My Bad"
- Mike Donovan - "Dexter"
- Jamie Jaworski - "Dexter"
- Matt Chambers - "Crocodile"
- Jorge Castillo - "Love American Style"
- Emmett Meridian - "Shrink Wrap"
- Little Chino - "Waiting to Exhale"
- Roger Hicks - "An Inconvenient Lie"
Note: In Early Cuts, Dexter also took a blood slide from The Lindquists.
Box Two Victims
- Adam Rowe - "My Bad"
- Alfred Norris - "My Bad"
- Arthur Mitchell - "The Getaway"
- Ben and Roger - "Those Kinds of Things"
- Benito Gomez - "Living the Dream"
- Boyd Fowler - "Practically Perfect"
- Cal Rooney - "Our Father"
- Christopher James - "Swim Deep"
- Clemson Galt - "Si Se Suede"
- Ethan Turner - "Turning Biminese"
- Fred Bowman - "Finding Freebo"
- Joe Walker - "Those Kinds of Things"
- Julio Benes - "Once Upon a Time..."
- Marvin Madden - "Swim Deep"
- Matt Parker - "My Bad"
- Michael Rose - "My Bad"
- Phillip Barnes - "Swim Deep"
- Stan Beaudry - "Hello, Dexter Morgan"
- Walter Kenney - "Smokey and the Bandit"
- Zoey Kruger - "Dex Takes a Holiday"
Victims that are shown on-screen or in flashbacks having, or implied to be having, their blood collected for a blood slide.
SEASON ONE - Trophies
- Alex Timmons (flashback) - First Box ("Return to Sender")
- Gene Marshall (flashback) - First Box ("Return to Sender")
- Cindy Landon (flashback) - First Box ("Return to Sender")
- Mike Donovan - First Box ("Dexter")
- Jamie Jaworski - First Box ("Dexter")
- Matt Chambers - First Box ("Crocodile")
- Jorge Castillo - First Box ("Love American Style")
- Valerie Castillo (used to frame her husband) ("Love American Style")
- Emmett Meridian - First Box ("Shrink Wrap")
SEASON TWO - Trophies
- Jimmy Sensio (not killed, slide washed) (It's Alive!)
- Little Chino - First Box ("Waiting to Exhale")
- Santos Jimenez (slide was presumably lost) ("Morning Comes")
- Roger Hicks - First Box ("An Inconvenient Lie")
SEASON THREE - Trophies
- Cal Rooney (flashback) - Second Box ("Our Father")
- Fred Bowman Second Box ("Finding Freebo")
- Ethan Turner Second Box ("Turning Biminese")
- Clemson Galt Second Box ("Sì. Se Puede")
SEASON FOUR - Trophies
- Benito Gomez Second Box ("Living the Dream")
- Zoey Kruger Second Box (Dex Takes a Holiday")
- Jonathan Farrow (later broken) ("Slack Tide")
- Stan Beaudry - Second Box ("Hello, Dexter Morgan")
- Arthur Mitchell - Second Box ("The Getaway")
SEASON FIVE - Trophies
- Marcetti - (implied in flashbacks) - First Box ("My Bad")
- Boyd Fowler - Second Box ("Practically Perfect")
- Cole Harmon - (given to Lumen Pierce) ("Take It!")
- Alex Tilden - Dexter did not keep slide as he was killed by Lumen ("In the Beginning")
SEASON SIX - Trophies
- Ben - Second Box ("Those Kinds of Things")
- Roger - Second Box ("Those Kinds of Things")
- Joe Walker - Second Box ("Those Kinds of Things")
- Julio Benes - Second Box ("Once Upon a Time...")
- Walter Kenney - Second Box ("Smokey and the Bandit")
- Travis Marshall - (slide broken, lost at crime scene) ("This is the Way the World Ends")
SEASON SEVEN - No Trophies
- Walter Munro (implied in flashbacks) - First Box ("Surprise, Motherfucker!")
- Dexter quit taking blood when he killed Ray Speltzer and destroyed his slide box, making this the first season where none of his victims had their blood taken. ("Run")
No Blood Taken
Dexter didn't collect blood trophies from at least 39 of his kills.
PRIOR TO BLOOD SLIDES - No Blood Taken
- Mary - ("Popping Cherry")
- Unnamed Victim - ("Every Silver Lining...")
- Unnamed Drug Dealer - ("Every Silver Lining...")
- Juan Ryness - ("There's Something About Harry")
- Robert Milson - ("Dark Echo - Chapter Two")
- Peter Thornton - ("Dark Echo - Chapter Five")
- Unidentified Victim - Identified via an official website
SEASON ONE - No Blood Taken
SEASON TWO - No Blood Taken
- Ken Olson - ("Dex, Lies, and Videotape")
- Jose Garza - ("There's Something About Harry")
- Esteban Famosa - ("Left Turn Ahead")
- Teo Famosa - ("Left Turn Ahead")
- Lila West - ("The British Invasion")
SEASON THREE - No Blood Taken
- Oscar Prado - ("Our Father")
- Nathan Marten - ("The Lion Sleeps Tonight")
- Camilla Figg - ("Easy as Pie")
- Miguel Prado - ("I Had a Dream")
- George King - ("Do You Take Dexter Morgan?")
SEASON FIVE - No Blood Taken
- Rankin - ("My Bad")
- Dan Mendell - ("Everything is Illumenated")
- Lance Robinson - ("Everything is Illumenated")
- Stan Liddy - ("Hop a Freighter")
SEASON SIX - No Blood Taken
- Nick - ("Just Let Go")
- Norm - ("Nebraska")
- Steve Dorsey - ("Ricochet Rabbit")
- Beth Dorsey - ("Talk to the Hand")
- Alberto - ("This is the Way the World Ends")
SEASON SEVEN - No Blood Taken
- Viktor Baskov - ("Are You...?")
- Ray Speltzer - ("Run")
- Unnamed Hitman - ("Argentina")
- Oleg Mickic - ("Helter Skelter")
- Clint McKay - ("The Dark... Whatever")
- Hector Estrada - ("Surprise, Motherfucker!")
SEASON EIGHT - No Blood Taken
- (Unknown Victims in six-month period between seasons)
- Unnamed Victim - ("A Beautiful Day")
- Andrew Briggs - ("A Beautiful Day")
- Ron Galuzzo - ("What's Eating Dexter Morgan?")
- A.J. Yates - ("This Little Piggy")
- Oliver Saxon - ("Remember the Monsters?")
- Debra Morgan - ("Remember the Monsters?")
- Kill Room
- Kill Tools
- Kill Ritual
- Dexter Morgan
- Dexter's Kill List
- Dexter's modus operandi
- Bay Harbor Butcher Case