Anna Kendrick is set to star in 'A Simple Favour'.

Anna Kendrick

Anna Kendrick

The 31-year-old actress has signed up alongside Blake Lively to join the cast of the thriller movie, which is based on an adaptation of the Darcey Bell novel of the same name.

'A Simple Favour' will be directed by Paul Feig in what will be his first foray into the thriller genre, where he will be working from a script penned by Jessica Sharzer.

The story - which is set to be the first of two planned books by Darcey - is a murder mystery which follows a famous fashion designer named Emily, who asks Stephanie - a widow who turns to her daily blog to help her feel less lonely - to pick up her son from school.

Stephanie - who also has a son - agrees and imagines Emily to be her new confidant, and is left stunned when the woman disappears and leaves her son and husband without a trace.

The novel only hit shelves in March this year, but it seems producers at Lionsgate can't wait to get started on the project, which is due to start filming in Toronto in August.

As of the time of writing, it is unknown which character Anna or Blake will play, or which stars will be cast to play their respective children.

Meanwhile, the 'Pitch Perfect 3' actress recently said she thinks she needs to start setting out clear goals and a path for herself as she keeps finding herself inundated with work and no time for a break.

She said: "There is no f***ing plan. I feel like I should get one, because that's why I end up in these situations where I'm shooting movies back-to-back and I don't want to stretch myself so thin that I'm not doing good work."