ITV's The Sister struck a nerve with viewers, as we were left to wonder how we would react if pushed to the extreme lengths that protagonist Nathan (Russell Tovey) is in the show, as he tries to hide his involvement in the disappearance of his wife's sister, Elise.
Ghosts and hauntings were key to the series, and if viewers were wondering if The Sister is based on real events (read more about The Sister true story), the four-part series is adapted from creator Neil Cross' book Burial, which in turn was inspired by a murderous nightmare The Sister creator Cross had - in addition to a haunting he claims to have experienced.
Haunted houses - and creepy nighttime groves - helped establish the unsettling, the show's horror-esque setting (see The Sister filming locations to find out more).
The first season's finale was open ended, with the suggested potential for a far more violent conclusion off-screen. Has ITV left it up to our imagination, or could there be a second season of The Sister on the cards?
Will there be a second season of The Sister?
Speaking exclusively to RadioTimes.com, Amrita Acharia (who played Holly) said she would "love" to be part of a second season - but nothing is in the works for the moment.
"I mean I would love that [a second season] purely because it's one of the most fun jobs I've done, because it was such a fun team, and the writing is just so good. I'd love there to be a second season. That's why they leave it open-ended isn't it? In my book [it is]. I don't know, I know as much as you do," she said.
Asked whether she thought there'd be scope for a season season, she said: "I think with a writer like Neil [Cross], I think there's scope for anything."
And would Acharia be on-board if she was offered a part on Neil Cross' rumoured next project: the Luther film? "Oh yeah, I'm in all the way - if Neil's written it."
What could happen in a second season?
*Warning: spoilers ahead for The Sister season one*
The Sister cast - including Russell Tovey and Amrita Acharia - would likely all return, including Simone Ashley as Elise, whose ghost is spotted in the very last seconds of the season one finale.
And while season one wrapped up plenty of loose threads and unanswered questions, there are still some remaining.
Will Bob (Bertie Carvel) wake up from the coma that Nathan put him in? Will Holly ever find out the truth about Nathan's involvement in her sister Elise's death? And did Elise's ghost appearing in the back of Nathan's car suggest that she was about to cause him to crash the car?