Fallout's Ella Purnell stars in killer trailer for Sweetpea thriller

"Suddenly the wallflower is gone, and in its place is a young woman capable of anything… Rhiannon's life transforms as she steps into a new, intoxicating power, but can she keep her killer secret?"

In the trailer, Purnell's character Rhiannon is introducing herself. While on first glance she seems perfectly normal, it's soon apparent there is more to her than meets the eye as she has a serious penchant for murder!

Listing the people who make her feel invisible, like her colleague Norman from work who fails to acknowledge her potential or Julia Blenkinsopp, the bully who ruined her life.

But Rhiannon also makes other lists, including of the people she'd "love to kill".

As the trailer continues, Rhiannon can be seen telling someone "don't push me" before it flashes to a shot of her covered in blood.

But it appears her thirst for murder may be catching up to her as someone begins piecing together a string of murders in a police boardroom.

"Don't underestimate me," she can be heard narrating over the video as someone says: "She's not who you think she is."

You can watch the full trailer below.

In addition to Purnell, the ensemble cast includes Nicôle Lecky (Sense8) as Julia, Jon Pointing (Big Boys) as Craig, Calam Lynch (Bridgerton) as AJ, Leah Harvey (Foundation) as Marina.

Further casting includes Jeremy Swift (Ted Lasso) as Norman and Dustin Demri-Burns (Slow Horses) as Jeff.

The six-part series has been adapted from CJ Skuse's novel of the same name.

Sweetpea will premiere on Sky and streaming service NOW in the UK on 10th October.

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