Darlene is a spider disguised as a human female who lures men that visit her tourist attraction called Mystery Mountain and traps them in cocoons to eat them.
She's introduced as the owner of Mystery Mountain, a tourist trap in Oregon that competes with Stanley Pines' Mystery Shack. When Stan tries to flirt with her, she pretends to be charmed, but the minute the two are alone, Darlene subdues him, webs him up and drags him into a cave to eat him. She shows her true form to him while bragging about how he fell straight into her trap and how she will eat him just like she did to countless other men. However, Mabel, Dipper, Candy and Grenda manage to save Stan and leave Darlene stuck under a giant statue's boot.
Darlene is an expert manipulator, skilled at taking advantage of men who think they are seducing her. Due to this, she looks down on men. She is one of the most evil characters in the show, as she clearly enjoys killing and eating humans and will gleefully mock her unfortunate victims.
She is surprisingly shrewd in exploiting her nature to her advantage in very disturbing and demented ways. Notably, her Mystery Mountain attraction boasts that it's inhabited by "spider people". Darlene effectively hides in plain sight, passing off her own existence as just a rumor. Similarly, she can get away with displaying the bodies of her webbed-up victims drained of their vital fluids by passing them off as mummies. The park promises "fresh mummies daily", implying that Darlene kills her visitors very often.
As a giant spider, Darlene has superhuman strength, and agility. Like all spiders she is able to cling onto almost any surface. She can produce very thick webbing that is almost impossible to escape from. It is unknown whether she has venomous fangs as well.
She is extremely durable as well, since being trapped under the boot of a giant statue was not enough to kill her, and in fact, she did not even seem to be in pain at all. Her chitin can be safely presumed to act as natural armor.
- Darlene may be a reference to the yokai Jorōgumo (lit. binding bride or whore spider) in Japanese folklore. This monster is a giant spider able to shapeshift into a beautiful woman.
- Darlene is a nod to the "black widow" archetype, women who seduce men before killing them for their money. In this case, the "black widow" is literally a spider, and her motivation is food rather than money.
- With her lower body in its true form and her upper body is disguised, Darlene resembles a drider (half-spider, half-dark elf creatures from the tabletop game Dungeons and Dragons.)
- Her "tourist trap" is also a literal trap.
- Her true nature is foreshadowed by her sunglasses, which resemble the eyes of her true spider form.
- Her final fate remains a mystery. While she was left trapped under a statue's foot, she was not killed, so it is not impossible that she could use her human form to convince a Mystery Mountain visitor to free her later.
- Darlene is notable by existing very far outside of Gravity Falls, where most of the other supernatural phenomena took place. She also refers to herself as part of a "species", which might mean that there are more creatures like her.