Christian Convery as Gus
The show's main character Gus is a hybrid and sets out on a journey to find his mum after leaving his home in the woods.
You may recognise 11-year-old Christian from Pup Academy as Morgan and he's also starred in Lucifer, Supernatural and Legion.
Nonso Anozie as Tommy Jepperd
Lone traveller Tommy joins Gus on his travels and eventually takes him under his wing.
If you're wondering where you recognise him from, Nonso played Xaro Xhoan Daxos in the second season of Game of Thrones and has also starred in the 2015 live action remake of Cinderella and fantasy flicks Ender's Game and Artemis Fowl.
Adeel Akhtar as Dr Aditya Singh
Dr Singh is, funnily enough, a doctor researching the virus also known as 'the sick' and will do anything for his infected wife Rani.
Actor Adeel has starred in films including The Big Sick and Netflix flick Enola Holmes as well as British TV shows like Killing Eve and Utopia.
Will Forte as Pubba
Gus' eccentric dad Pubba raised his son in a remote cabin in Yellowstone National Park in an effort to protect his son.
You've no doubt seen Will Forte in various comedy TV shows and films including Saturday Night Live, 30 Rock and The Lego Movie films.
Dania Ramirez as Aimee Eden
Former therapist Aimee takes shelter in abandoned zoo after The Great Crumble and sets up a safe haven for hybrid children.
If you've ever seen The Sopranos, Heroes, Entourage or Once Upon A Time, you may recognise Dania.
Stefania LaVie Owen as Bear
Teenage leader of the Animal Army, Bear is on a mission to protect hybrids.
The New-Zealand-American actress is known for her roles in The Carrie Diaries and Running Wilde.
Aliza Vellani as Rani Singh
The infected but non-contagious wife of Dr Aditya Singh, Rani lives a relatively normal life at home with her husband.
Aliza has starred in Riverdale, iZombie and The X-Files.
Neil Sandilands as General Steven Abbot
Leader of the Last Men, General Abbot is on a mission to rid the world of hybrids.
The villainous character is played by Neil Sandilands who's starred in action series The 100 and The Flash.
Mia Artemis as Tiger
Tiger is one of the members of Bear's gang, The Animal Army.
Aussie emerging star Mia will appear in Toni Collette’s Netflix thriller Pieces of Her, set to be released later in 2021.
James Brolin as The Narrator
He may not make a physical appearance on screen, but the Hollywood actor famed for his role as Steven Kiley in Marcus Welby, M.D who is also Barbara Streisand's husband, can be heard narrating the series.