"Why does this always happen to me?!"
―Sylvester Siler after being shocked.[src]

Sylvester "Sly" Siler is a Master Sergeant in the United States Air Force and technical expert at Stargate Command.



He was responsible for overseeing the repairs on the Stargate when it overloaded and sent Captain Samantha Carter and Colonel Jack O'Neill to the Beta Gate in Antarctica. (SG1: "Solitudes")

He attempted to cut through the Virus Orb after it opened and one of the spikes pierced Colonel Jack O'Neill's shoulder. When he was about to cut through the orb reacted and moved the cut portion into the wall. (SG1: "Message in a Bottle")

When Stargate Command was dialed into P3W-451, he and Colonel Jack O'Neill attempted to shut down the power to the Stargate in the Stargate Command power vault. Unfortunately, the circuit breakers overloaded and he was severely burned. He recovered and aided Carter, O'Neill, Teal'c and Colonel Frank Cromwell detonate a shaped charge to cause the wormhole to jump. (SG1: "A Matter of Time")

When Major Samantha Carter and Teal'c along with two other SG team members were trapped on P9Q-281, he worked on solving the problem with the Dial Home Device but was unsuccessful. After O'Neill figured out a solution, he was given the Power booster device to study by Dr. Daniel Jackson. (SG1: "The Fifth Race")


When Sokar bombarded the Iris with a Particle accelerator, he used Liquid nitrogen to cool the Iris in order to keep the heat from affecting the Dialing computer. (SG1: "Serpent's Song")

During a Foothold situation at Stargate Command, the Stragoth used the Mimetic imaging device to impersonate him. (SG1: "Foothold")


When SG-1 found a crystal skull on the planet P7X-377 and Dr. Daniel Jackson disappeared, he and Dr. Robert Rothman were assigned to study it but could not determine its function. (SG1: "Crystal Skull")

When SG-1 beamed the Alpha Gate to the Biliskner, he supervised the installation of the Beta Gate at Stargate Command. He then traveled to the Naval base where the Blackbird was docked and helped to coordinate the destruction of the Replicators. (SG1: "Small Victories")

When Stargate Command began negotiating with the Eurondans, Major General George S. Hammond ordered him to round up the first shipment of heavy water. (SG1: "The Other Side")

When Colonel Jack O'Neill had the Atanik armband on and patted Siler on the shoulder, the sheer force pushed Siler off a ledge. He sustained a broken arm and concussion in the process which resulted in O'Neill, Samantha Carter and Daniel Jackson being put under guard. (SG1: "Upgrades")

During the time loop, he continuously ran into Dr. Daniel Jackson in the halls of Stargate Command. (SG1: "Window of Opportunity")


When an Entity from P9C-372 entered the Stargate Command mainframe, he assisted Major Samantha Carter in shutting down the system to eradicate it. (SG1: "Entity")

He coordinated with Major Wood in transferring the rocket through the Stargate to K'tau. (SG1: "Red Sky")


When Teal'c was trapped in the Stargate, he connected the Russian Dial Home Device to the Gate to get him out. (SG1: "48 Hours")

When Reese barricaded herself in the Embarkation room, he used a welder to cut through the blast-door. (SG1: "Menace")

When SG-1 went missing and NID Colonel Frank Simmons took over the SGC, he helped Major General George S. Hammond and Harold Maybourne to surreptitiously enter Stargate Command and travel to Chulak without Simmons being the wiser. (SG1: Survival of the Fittest)


When Colonel Jack O'Neill and Harold Maybourne went missing on P5X-777, he launched an Unmanned Aerial Vehicle to search for them. (SG1: "Paradise Lost")

He was assisting Major Samantha Carter overhauling the Stargate's capacitors when they overloaded. He suffered a burn on his hand and Carter was knocked unconscious but quickly recovered. (SG1: "Prophecy")

He assisted Jacob Carter in putting on the Kull armor and made a joke about his age. (SG1: "Evolution, Part 2")


When the Alpha Site was attacked by Anubis, he was ordered by Major General George S. Hammond to prepare an Unmanned Aerial Vehicle with UCAV specs. (SG1: "Death Knell")

He tested Dr. Bill Lee's new vest insert by allowing Teal'c to shoot him in the stomach with a Staff weapon. The insert stopped the blast and he received only minor burns. (SG1: "Heroes, Part 1")

He assisted Dr. Rodney McKay in installing the Zero Point Module into Stargate Command in hopes of dialing Atlantis in the Pegasus galaxy. (SGA: "Rising")

When a plant from P6J-908 affected power throughout Stargate Command, he worked with MSgt. Walter Harriman to get the Stargate back online. (SG1: "Zero Hour")

In the final version of the simulation Teal'c got trapped in by the virtual reality pod, Siler was a Goa'uld infiltrator. After Siler was revealed as the infiltrator, he was killed by Teal'c with an FN P90 Personal Defense Weapon, ending the simulation. (SG1: "Avatar")


When the Replicators invaded Stargate Command, he was trapped on Level 8 and was freed by Brigadier General Jack O'Neill and Colonel Albert Reynolds. They held the Replicators at bay while he attempted to dial the Alpha Site. He was unable to do so because of an incoming wormhole from Dakara that destroyed the Replicators. (SG1: "Reckoning, Part 2")


He was part of the team that went offworld to check Nerus for weapons before allowing him to come to Stargate Command. (SG1: "Beachhead")

Siler was studying the rear control panel of a Puddle Jumper in Stargate Command before he was shot with a Zat'nik'tel by Lt. Colonel John Sheppard. (SGA: "The Return, Part 1")

He assisted Dr. Bill Lee in setting up Symbiote poison canisters in the Stargate Command ventilation system. (SG1: "Insiders")


Appearances for Sylvester Siler

In chronological order:

Personal life

Siler sometimes helps Samantha Carter work on her motorcycle. He has a set of pajamas given to him by Jack O'Neill. In 2004, O'Neill said that his collection of The Simpsons video cassettes will go to Siler. One year later, he learned that he was in Siler's will. (SG1: "The Curse", "Lost City, Part 2", "Reckoning, Part 2")


This section requires expansion


Other equipment


  • Because of Shea's lisp, the writers would often give him lines with a hard S, such as "Sorry Sir". Dan Shea would say it as "Thorry Thir"; which would also explain both his first and last name. However, in season 4, his name was Dan Siler.
  • Siler has a tendency to be the victim of electrical shocks because of his work with the high-powered Stargate, though none of these have been life-threatening so far. As a running gag, he is often injured, either by the electrical systems, enemies, alien devices, his own wrench (the one needed for the capacitors of the Stargate), or "tests." After an incident in "200" in which the Stargate malfunctions and an electric shock hurls him across the room, Siler mutters, "Why does this always happen to me?!" (albeit this was a story fabricated by Martin Lloyd). Once he even walked head-on into a door that he had not noticed due to being distracted by a passing Samantha Carter and Vala Mal Doran who had returned to base while both stunningly dressed up from a night of shopping.[1]
  • Along with Jack O'Neill, Daniel Jackson, Samantha Carter, Teal'c, George S. Hammond and Walter Harriman, he is one of only seven characters to appear in all ten seasons of Stargate SG-1. Of these, Siler is the only one who did not appear in "Children of the Gods".


External links

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