The story of Dr Gemma Foster, played by Suranne Jones, uncovering her husband's affair and carrying out some pretty surprising plans as a result gripped the nation, with an impressive 10.1 million of us tuning in for the finale when it aired in October 2015.
And now, the BBC have released a chilling sneak peek at what could be in store the second time around, with a dramatic image of Suranne with blood on her hands and a menacing stare on her face.
Back in May, a trailer promoting all of the exciting BBC dramas for this season has given a glimpse into the remains of the couple's relationship.
In the tantalising short clip, Gemma's husband Simon is seen telling her: 'There's only one way I'm leaving right now, and that's in a coffin,' to which she chillingly responds: 'That's good to know.'
Most of the details about Doctor Foster series two have been kept tightly under wraps, but here's what we know so far (and all of the details of season one if you need a refresher!)
What did I miss last time?SPOILER ALERT - we're basically going to tell you the plot of series one, so avert your eyes if you want to watch it for yourself...
Gemma suspects her husband, property designer Simon, of having an affair - possibly with his assistant Becky, but later discovers that it's not Becky Simon's seeing at all. It's Kate Parks, the daughter of one of her patients, and - gasp - she's pregnant.
Gemma confronts Simon, and he denies all knowledge, but his elderly mother Helen tells Gemma that the infidelity has been going on for two years.
As she unpicks the truth and takes her revenge, she makes some questionable choices herself, including sleeping with Simon's accountant in order to blackmail him about a bankrupt project Simon's involved in, and encouraging another of her patients, Carly, to befriend Kate and gain her trust.
Things come to a head over a seriously tense dinner at Kate's parents' house, where the truth tumbles out, and the finale climaxes with Gemma pretending to abduct the couple's son Tom to scare her husband into submission - a move that causes him to eventually attack her.
When we left the characters, Gemma had gained full custody of Tom and filed for divorce, while now-penniless Simon and Kate had welcomed their baby. So what happens next?
What's going to happen in Dr Foster series two?As we mentioned, the BBC is keeping most of the plot points on lockdown, but we do know that the story is going to take a big time jump, and will be set around two years in the future.
Suranne has said that the series will explore 'what happens to a woman after divorce, deceit and revenge has taken its toll', adding that it won't just be a repeat storyline of series one.
'I felt like my story had finished,' she said. 'But then when they told me what they wanted to do with it, I felt that nothing had been done on television like it.'