First seen
Last seen
"At All Costs" (mentioned only)
Appeared in
Mentioned in
Also Known As
Espheni Weapons
Date of birth
Date of death
Family members
Portrayed by


Those things can eat through metal!
— Matt upon seeing the creature's tunnels.

Crawlies are creatures featured in Season 2's episode Molon Labe. They are apparently in the employ of the Espheni. They are deployed when the Espheni need to infiltrate a position to take it by surprise instead of their more typical frontal assaults.


The origins of the Crawlies is unknown. They may be another species enslaved by the Espheni with harnesses or willing allies. They may not even be sentient at all, just animals domesticated and trained by the Espheni to track down prey like human hunting dogs.

They are first encountered in the basement of the hospital after the 2nd Mass captures an Espheni; apparently sent by the aliens as a means to force the humans to surrender their captive. They kill Jamil Dexter by infesting him like a Trojan horse and trap Lourdes, Matt, and Anne in the basement. Matt manages to escape and gets help by crawling through the vents; running into Tom and Pope and some of the others who get him to safety and rescue them.

The 2nd Mass manage to trap the creatures in the basement, but they can eat through metal. It is unknown what happened to them after the 2nd Mass left the hospital, it is possible they were controlled and forced back to the Espheni.

Weaver mentions them during the Siege of Charleston. Weaver is worried the Espheni might try to catch the defenses around Charleston off guard by sending in Crawlies for a sneak attack, but they do not.


No Crawlies have ever been seen utilising any form of technology.


Crawlies have vaguely arachnid-like features (albeit with six insect-like limbs instead of eight). They are about the size of a human hand and are a dull grey in colour with blue strips along their torso. They have two small eyes and a flat head with a broad mouth structure similar to that of a skitter. These jaws are strong enough to eat through metal.

Crawlies appear to be natural burrowers: small enough to slip into enemy structures unnoticed through vents and air ducts, and with time they can bore their way through barriers they may encounter such as doors.

While durable against melee-weapons, they can be killed by gunfire without too much trouble. However, they appear to be pack hunters, deploying in large numbers and using swarm tactics to overwhelm opposition similar to Army Ants.

When attacking they can rear up on their four hind legs and use their pair of forelegs like a Preying Mantis. They can also hide in a body and burst out in a manner of a trojan horse (whether or not this is a mode of reproduction is unknown).

Not much else is known about Crawlies biology. It's unknown if they have an exoskeleton - like terrestrial insects and arachnids - or an internal bony endoskeleton. However they appear very durable, irrespective of how their bodies supports are structured, as they can withstand several hits by the butt of a rifle before death (According to Hal it took fifteen hits to kill one). Their muscles and circulatory system are also unknown.

Crawlies are apparently not sentient or self-aware, and are more like living weapons or pack animals that the Espheni unleash on their enemies. It is unknown if they possess some form of higher hive-intelligence (based on the telepathic connection the Espheni have been shown to possess with their other slave races).

Given that the Skitters themselves were mutated from some unknown stock using the harnesses, it is unknown if the Crawlies as they currently appear are what their natural form was like on their home planet, or if the Espheni mutated and bred them from a different original form which they twisted to their own purposes. The Espheni may have even bio-engineered them from scratch.


Nothing is known about Crawlies society and beliefs, assuming they even have any, other than the fact that they appear to be a collective species like Ants or Termites.

Known IndividualsEdit

No Crawlies have ever demonstrated individuality. This may be due to having a hive mind mentality (they appear to swarm and move in unison) or they may not be intelligent at all.

Behind the ScenesEdit

The Crawlies haven't received a formal name so far. They didn't receive a name in the second season episode they debuted in, but in Molon Labe Matthew Mason refers to them as "Crawlies". They are subsequently referred to as such by other characters.