When a witch becomes pregnant with a vampire's child, Season 3 of "The Witches' Big Adventure" goes into all-out war. Diana Bishop (Teresa Palmer) and Matthew Claremont (Matthew Goode) face off against the powers that rule the creature world in the final season of the supernatural drama. It will air on Sky One in the UK and on AMC Plus, Sundance Now, and Shudder in the US.

In the previous episode, "The Discovery of the Witches," Diana and Matthew returned to London in 1590 to hide from the ruling congregation long enough for Diana to master her magical abilities.

In Season 3, they return to the present day to find tragedy has struck the Sept Tours. The couple scrambles to find the lost pages of the Book of Life and the Book itself before it is too late, but a monster from Matthew's past awaits his return.

What we know so far about "The Witch's Delivery Service" Season 3 is as follows.

Sundance Now, Shudder, and AMC Plus have set a U.S. release date of Saturday, January 8, 2022 for "The Witches' Big Discovery" Season 3; AMC Plus includes Shudder and Sundance Now, and some of the best streaming device with apps on them (available on Roku, Amazon Fire TV, and Apple TV); AMC Plus is also available as an add-on to Sling TV (one of our picks for the best streaming service).

In the UK, Season 3 of "The Witches' Big Adventure" will premiere the day before, on Friday, January 7.

The release date announcement did not confirm whether all Season 3 episodes would be available simultaneously. In the UK, Season 2 was broadcast all at once and aired weekly on SkyOne. In the US, however, episodes were only broadcast weekly. Our guess is that season 3 will follow the same schedule.

The first teaser trailer for Season 3 of The Witch's Delivery Service opens with a shot of a pregnant Diana in Matthew's arms. The ominous voiceover notes, "Anything that threatens the existing order must be extinguished." It is a war that cannot be won, we hear Matthew say. But Diana will not allow it. Let them come," she warns.

The Witch's Delivery Service stars two main characters: Teresa Palmer as Diana Bishop, a witch and historian, and Matthew Goode as Matthew Claremont, a vampire and Oxford University professor of chemistry.

They are joined by:

The Witch's Delivery Service Season 3 will also include new faces. Toby Legbo, Matthew and Diana's adopted son, was cast as an older version of Jack, an orphan they took in in London in 1590.

Ivanno Jeremiah plays molecular biologist Christopher Roberts.

Olivier Huban, Parker Sawyers, and Genesis Rainea were cast as vampires.

Season 3 of The Witches' Great Adventure is adapted from The Book of Life, the final book in Deborah Harkness' All Souls trilogy. As such, there are spoilers from the novel ahead!

Diana and Matthew return from 16th century London and embark on a mission to find the lost pages of The Book of Life. They also seek revenge against the Friars for the death of Diana's Aunt Emily.

Their biggest priority is to protect the twins growing inside Diana, who threaten the existence of the Congregation. But the witches Peter Knox and Satu Järvinen are not their only enemies; the bloodthirsty vampire Benjamin Hooks is also after them.

Matthew must face the consequences of his past while working with scientists at Yale University to find a way around the Congregant's ban on inter-species marriage and procreation. Meanwhile, Diana hones her powers so that once they complete the Book of Life, she will be able to unlock its mysteries.