Carey Mulligan is to star in 'Fingernails'.

The 35-year-old actress has joined the cast of the romantic drama which marks the English-language feature film debut for Greek director Christos Nikou.

The movie follows a woman called Anna (Mulligan), who increasingly suspects that her relationship with her long-time partner might not be the real thing. In an attempt to improve things, she secretly embarks on a new assignment working at a mysterious institute designed to incite and test the presence of romantic love in increasingly desperate couples.

Nikou is collaborating with Dirty Films and executive producers Cate Blanchett, Coco Francini and Andrew Upton – who all worked Nikou's current movie 'Apples', which premiered at the 2020 Venice Film Festival.

Christos is writing the script with playwright Sam Steiner and 'Apples' co-writer Stavros Raptis.

The director said: "'Fingernails' explores the modern experience of falling in love at a time when – though it seems more accessible than ever – romance has becomes so uncertain, complicated and elusive.

"We created the role of Anna with Carey in mind and are thrilled that she said yes immediately. Carey is such a talented and magnetic actress, and I was blown away by her performance in 'Promising Young Woman'.

"I am more than excited to begin work with Carey and bring 'Fingernails' to life in collaboration with my producers Cate Blanchett, Coco Francini and Andrew Upton at Dirty Films."

Dirty Films added: "After our partnership on 'Apples', we couldn't be happier to continue our collaboration with Christos Nikou on 'Fingernails'. In a time when finding human connection is more important and more challenging than ever, Christos' tender and refreshing take on modern romance is unique and profound.

"We feel Carey Mulligan – who we have long admired for her powerful and buoyant performances – is the perfect actor to help capture the surreal fizz and genuine heartache that fuels this brilliant vision."