In the desert town of Night Vale, all conspiracy theories are real. Scientists knock on the door of a house that does not exist. A faceless old woman lives in your home, rearranging your books and demanding your Wi-Fi password. Mysterious lights pass overhead while everyone pretends to be asleep.

These are all part and parcel of the morbidly funny Welcome To Night Vale, a cult podcast that takes the form of a community radio show set in a fictional town in the American south-west, where residents are so plagued by bizarre perils - from dark hooded figures to a glow cloud that rains dead animals - that they regard them as mundane.

Created by American writers Joseph Fink and Jeffrey Cranor, the weird world of Night Vale has recently branched out into fiction, first with the inaugural Welcome To Night Vale novel in 2015, which they followed up last year with It Devours!, a kooky thriller about science and religion.

Fink, 31, says he and Cranor, 42, began writing the novels to explore Night Vale outside the perspective of the radio show, on which host Cecil Palmer reports, often with cheery nonchalance, on the town's macabre happenings.

"These novels are a way to tell newer, bigger stories in the same world," he says over Skype from Portland, Oregon, where he is touring with the Welcome To Night Vale live show.

The first novel, a New York Times bestseller, is told from the perspectives of Jackie Fierro, who has been stuck running a pawnshop as a 19-year-old for decades, perhaps centuries (time does not work in Night Vale) and Diane Crayton, the single mother of a shapeshifting teenager.

In It Devours!, scientist Nilanjana Sikdar investigates the phenomenon of great pits appearing suddenly around town and finds herself embroiled in a doomsday cult that worships a ravenous entity called the Smiling God.

"We wanted the book to be about science and religion and the way they intersect in people's lives," says Fink. "These subjects are often talked about in conflicting terms, which is a really simplistic way of looking at them."

As a scientist, Sikdar is considered a foreigner in Night Vale, where townspeople literally refer to her as "Outsider".

"We wanted to have some fun with someone who recognises the weirdness of Night Vale," says Fink, who is married with no children.

He notes, however, that there are plenty of weird and dangerous things in the real world. "There are things that can randomly kill you at Night Vale and that's also the case in the real world - just that in Night Vale, it's aliens, not disease."

He has seen his fair share of weirdness while touring America. Once, while driving in Montana, he saw a black, windowless tower coming out of a mountainside. "It looked like something out of The Lord Of The Rings. It looked like it didn't belong in the real world."

The tower turned out to be the ventilation shaft of an abandoned mine. Fink went on to work it into the first episode of his podcast Alice Isn't Dead.

Fiction has presented a new challenge for him and Cranor. "A podcast is just 25,000 words long, whereas a novel is 80,000 to 100,000 words."

For a podcast, he adds, one can go into the episode with a single phrase in one's head - such as "wheat and wheat by-products", a random phrase that he later spun into an episode in which all the wheat and wheat by-products in Night Vale transform into venomous snakes.

"For a novel, you have to think about it in a much bigger way - what is this about, where is it going, how do I want it to end?"

Fink and Cranor started Welcome To Night Vale in 2012 after they met through the theatre collective New York Neo-Futurists and decided they enjoyed collaborating.

Since then, the twice-monthly podcast has been downloaded more than 180 million times worldwide and turned into a live show that has toured 16 countries. A television adaptation by FX is in the works, with Fink and Cranor as executive producers. They are also working on a third novel.

There is a dystopian bent to Night Vale, where the City Council has banned numerous things such as computers, writing utensils and the aforementioned wheat and wheat by-products. Residents are monitored around the clock by the secret police, who abduct family members of voters during election season. "Remember, this is America!" Palmer reminds his listeners. "Vote correctly or never see your loved ones again."

Fink is concerned his own reality is following suit, given the turmoil following the election of Mr Donald Trump to United States President in 2016. "When you write dystopian fiction, it's not great when real life starts to look like your fiction."

He cites the example of Mayor Pamela Winchell, a character who gave absurd press conferences and once hid behind a tree pretending the journalists assembled were not there. He compares this with former White House spokesman Sean Spicer, who, during a presidential press conference, huddled among bushes while reporters sought to question him.

"That was a funny little thing we wrote and then Sean Spicer stole Winchell's bit. That was a weird moment for us."

Fink hopes the show, while maintaining its surreal humour, will continue to be "useful" in a time of creeping dystopia. "We try to write towards what's happening. We are hoping our work reflects the world."

• Welcome To Night Vale ($18.95) and It Devours! ($38.52) are available at Books Kinokuniya.