Have you noticed strange ads on the TTC lately? You're not alone. A number of people have taken note of the Hawkins Power and Light posters popping up across the system.

Who's signing up for Hawkins Power and Light?! #StrangerThings #TTC pic.twitter.com/SH57NYJ3SW

— Kristie Andrews (@KristieAndrews3) October 25, 2017

They seem innocent at first — just wholesome advertising for a lighting company — but fans of the show Stranger Things know they're actually more sinister than they appear.

Without spoiling too much, Hawkins is actually a front for an insidious group that's experimenting on children.

I like how I'm seeing "Hawkins Power and Light" ads in the subway

— 👻Alvin BOOnaag👻 (@CipherGem) October 30, 2017

The ads are a hidden promotional piece for the second season of the Netflix show, which was just released last week. They've also been spotted in Los Angeles and New York.

The new ads show an adult playing delightfully with a child, which further adds to their creepiness for fans of the show.

Call the phone number

— Joey (@8FloorsAbove) October 21, 2017

The best part (or worst depending on your perspective)? The phone number on the ads actually works. We’ll leave it up to you to call and see what happens.