American Horror Story: Freak Show returns this Wednesday, 8 October, with the fourth installment of its critically acclaimed anthology series.

The season 4 premiere episode is titled Monsters Among Us and the official synopsis reads:

One of the only surviving sideshows in the country struggles to stay in business during the dawning era of television. When police make a terrifying discovery at a local farmhouse, the eccentric purveyor of the freak show sees an opportunity that will lead her troupe either to their salvation or ruin.

American Horror Story creator Ryan Murphy warned those with a weak heart are at risk of having heart attacks, describing this season as the scariest one yet.

Murphy told Buzzfeed News, "We said in the writer's room that if we were going to do clowns, we were going to create the most terrifying clown of all time. That was our goal when we were writing him… I'm worried that people are going to have cardiac arrests…"

Murphy told Entertainment Weekly: "Twisty the Clown [played by John Carroll Lynch] is a murderous clown and he's furious that the freaks have shown up in a town where he, the most evil clown of all time, has retired and he's out to make their lives a living hell."

He also revealed that the Twisty the Clown will be seen wearing a mask to cover his lower side of the face, and teased that if someone sees what he is hiding under the mask, they will "faint in terror".

Here are the teaser trailers, released by FX Network.