Joss Whedon's HBO Sci-Fi Series 'The Nevers' Sets Main Cast

The new Joss Whedon supernatural period drama has set its main cast. The Nevers cast has been announced by HBO, with 12 actors comprising the main ensemble for the sci-fi series following a gang of Victorian woman who find themselves with "unusual abilities." Outlander's Laura Donnelly has already been announced as the lead in the HBO series, but joining her in The Nevers are several Whedon alums and major stars, including Olivia Williams, Nick Frost, and Denis O'Hare.

Entertainment Weekly has the full cast list and character descriptions for the main cast of The Nevers which, in addition to Donnelly, Williams, Frost, and O'Hare, include Grantchester's James Norton as a "pansexual posh boy," Snowden's Ben Chaplin as a gruff "deeply moral" detective, and Poldark's Eleanor Tomlinson as a gentle failed singer. Donnelly leads the cast as a "reckless" and emotionally damaged heroine who discovers supernatural abilities and embarks on a mission that may change the world.

The series is Whedon's highly anticipated return to television following the Buffy the Vampire Slayer and Firefly creator's dalliance with Marvel superheroes, and the premise sounds like classic Whedon. A cheeky heroine, a colorful and diverse ensemble, and a recognizable Whedon alum like Williams, who last worked with Whedon on the underrated Dollhouse. Williams will be playing the second major role after Donnelly, as a wealthy spinster and champion of the "Touched," the women who have supernatural abilities. Frost, meanwhile, continues what appears to be a scene-stealing streak on TV, following up a role in AMC's Into the Badlands with his The Nevers role of "The Beggar King."

See the full cast list below.

Laura Donnelly (Outlander) as Amalia True (previously announced) – The most reckless, impulsive, emotionally damaged hero of her time. A menace to stuffy Victorian society, she would die for the cause and kill for a drink.

Olivia Williams (Dollhouse) as Lavinia Bidlow – A wealthy spinster and champion of the "Touched," Lavinia funds the Orphanage (where Amalia and many of the Touched live) through her vast family fortune. She is stern and old-fashioned, but as strong-willed and clever as anyone she confronts.

James Norton (Grantchester) as Hugo Swann – A pansexual posh boy whose charm has about five years left on its lease.  He runs a secret club and a side trade in blackmail. He's devoted to fulfilling everyone's worst impression of him — and fascinated by the Touched.Tom Riley (Da Vinci's Demons) as Augustus "Augie" Bidlow – A sweet, disarming nerd and Lavinia's younger brother.  A keen ornithologist, Augie is happy to let his older sister take the reins of the family fortune. He finds the Touched unnerving, but is drawn to them by his increasing infatuation with Miss Adair, and by the schemes of his nefarious best friend, Hugo.

Ann Skelly (Little Women) as Penance Adair – Amalia's dearest friend, and one of the first women to join her cause. A devout — yet heretically progressive — Irish girl, Penance has genius for invention. She is delighted by her power, and her default is love and acceptance. But she's firm in her moral sense, and will be guided by what's right over what's expedient every time.

Ben Chaplin (Snowden) as Detective Frank Mundi – Big, gruff, and deeply moral, Detective Mundi trusts no one, least of all himself: his reputation for sudden violence (and excessive drink) is not unwarranted. Frank finds himself caught between the powerful, who ignore the laws of the land, and newly empowered, who ignore the laws of physics.

Pip Torrens (The Crown) as Lord Massen – Staunch, unflappable and merciless in his defense of the British Empire, this former General, now Peer, may be the only man who sees clearly what havoc these few strange people can wreak upon the established order. Which he will protect, one way or another.

Zackary Momoh (Seven Seconds) as Doctor Horatio Cousens – One of the few successful West Indian physicians in London.  Married with a young son, Horatio's fortunes took a dark turn when he met Amalia and discovered his own ability. Now he works with her, and with the Beggar King, those who don't care who is or isn't "different."

Amy Manson (Being Human) as Maladie – Committed by her husband (and genuinely unstable), she's been warped by a power she can't understand, and tortured by doctors intent on finding its source. She now lives underground, runs a gang and is on an infamous murder spree. She affects a theatrical parody of a bedlam waif, but mad as she is, she's a woman with a purpose.

Nick Frost (Shaun of the Dead) as Declan Orrun, aka The Beggar King – Charismatic and brutal, Declan runs — or has a piece of – most of the low-level criminal activity in the city. He's perfectly happy to help Amalia and her cause — and equally happy to sell them out.  He backs winners, and the Touched are long odds.

Rochelle Neil (Episodes) as Annie Carbey, aka Bonfire – Annie is a career criminal who landed the ability to control fire and is happy to hire it out. Came up rough, stayed that way, but she's neither impulsive nor cruel — just looking out for herself. No matter who she works with or for, Annie trusts only Annie, and the fire.

Eleanor Tomlinson (Poldark) as Mary Brighton – Gentle but surprisingly resilient, Mary pursued her dream of singing on stage. A disappointing career and a broken engagement haven't diminished her spirit. She's going to be great. She's going to be very surprised how.Denis O'Hare (Big Little Lies) as Dr. Edmund Hague – A gifted American surgeon, he uses his skills in the coldest, most brutal way possible. But it's all in the name of progress!

As crowded as this ensemble already is, HBO noted that there's more casting to come, so keep an eye out for that. The Nevers doesn't yet have a premiere date.