The Catastrophe creator is setting the show Out There in the world of technology and dating.
The actor, writer and producer has already written other hugely successful shows, such as HBO's Divorce which starred Sarah Jessica Parker (inset).
The new series will be based on a New Yorker short story by Kate Folk, who will write the show with Horgan.
It tells the story of Meg, a lonely and single woman in San Francisco, who thinks she's found the perfect partner in Roger, a disarmingly handsome, attentive and empathetic man.
But she soon discovers he's a blot - a fake man programmed to steal her identity, ruin her reputation and destroy her life.
The half-hour show is set in a world where technology has been weaponised to exploit our deepest fears and desires.
According to showbiz website Deadline, it explores intimacy, modern dating and how much we'd be willing to sacrifice for a genuine connection.
It is the latest Hulu project for Horgan, who produced and starred in comedy series This Way Up, created by Aisling Bea, for the streaming giant.
She can currently be seen in the second series of Netflix's Criminal, joining Game of Thrones star Kit Harington and The Big Bang Theory's Kunal Nayyar in the police interrogation drama.
Out There is based on Folk's story of the same name, published in March after the author tried her hand at online dating.
"I wrote my first blot story a few years ago, during one of my forays into online dating," said Folk.
"I know many people enjoy using dating apps but at the time they felt to me like another alienating offshoot of the tech industry that dominates San Francisco - where I've lived since 2008.
"My work often explores the notion of the uncanny and how technology, especially in the form of mediated communication and artificial intelligence, can tap into our deepest societal and personal anxieties."