Watts is particularly known for her work in remakes and independent productions with dark or tragic themes, as well as for portrayals of characters who endure loss or suffering.

[4][5] She is the daughter of Myfanwy (Miv) Edwards (née Roberts), an antiques dealer and costume and set designer,[4] and Peter Watts (1946–1976), a road manager and audio engineer who worked with Pink Floyd.

[12][13] Following his death, Watts's mother moved the family to Llanfawr Farm in Llangefni and Llanfairpwllgwyngyll, towns on the island of Anglesey in North Wales, to live with her parents, Nikki and Hugh Roberts.

"[11][29] In 1996, she starred alongside Joe Mantegna, Kelly Lynch and J. T. Walsh in George Hickenlooper's action-thriller Persons Unknown; alongside James Earl Jones, Kevin Kilner and Ellen Burstyn in the period drama Timepiece; in Bermuda Triangle, a TV pilot that was not picked up for a full series, where she played a former documentary filmmaker who disappears in the Bermuda Triangle;[33] She had the lead role in Children of the Corn IV: The Gathering, in which children in a small town become possessed under the command of a wrongfully murdered child preacher.

[12] In 1998, she starred alongside Neil Patrick Harris and Debbie Reynolds in the TV film The Christmas Wish, played the supporting role of Giulia De Lezze in Dangerous Beauty,[19] and provided some voice work for Babe: Pig in the City.

Mulholland Drive, also starring Laura Harring and Justin Theroux, premiered at the 2001 Cannes Film Festival to high critical acclaim and marked Watts's breakthrough.

Reviewing her performance, Peter Bradshaw of The Guardian stated that "Watts's face metamorphoses miraculously from fresh-faced beauty to a frenzied, teary scowl of ugliness.

";[41] Emanuel Levy wrote, "... Watts, in a brilliant performance, a young, wide-eyed and grotesquely cheerful blonde, full of high hopes to make it big in Hollywood.

"[48] In the same year, she also starred in Rabbits, a series of short films directed by David Lynch; alongside several other famous British actors in the black comedy Plots with a View; and with Tim Daly in The Outsider, a western.

In 2003, Watts took the part of Julia Cook in Gregor Jordan's Australian film Ned Kelly, opposite Heath Ledger, Orlando Bloom and Geoffrey Rush.

Roxeanne and her sister Isabel (played by Kate Hudson) dispute the ownership of a painting by Georges de La Tour with the family of Charles-Henri's lover.

[51] In the story, told in a non-linear manner, she portrayed Cristina Peck, a grief-stricken widow living a suburban life after her husband and two children were killed by Jack Jordan (Benicio del Toro).

"[55] In 2004, Watts starred alongside Mark Ruffalo in the independent film We Don't Live Here Anymore,[12] based on short stories by Andre Dubus.

[70][71][72][73] Her other 2005 film release was Marc Forster's psychological thriller Stay, alongside Ewan McGregor, Ryan Gosling and Bob Hoskins.

[75] She is not prepared when her husband goes to Hong Kong, then a British colony, for work and then forces her to mainland China to a region suffering a cholera epidemic.

Comparing her portrayal with Greta Garbo's in the original movie adapted from the same novel, the San Francisco Chronicle wrote, "Watts makes the role work on her own terms–her Kitty is more desperate, more foolish, more miserable and more driven... and her spiritual journey is greater.

[99] Her portrayal of Valerie Plame in the biographical thriller Fair Game followed,[100] and marked the third pairing of Watts with Sean Penn after 21 Grams and The Assassination of Richard Nixon.

[103] In 2011, she appeared with Daniel Craig and Rachel Weisz in Jim Sheridan's psychological horror film Dream House, as the neighbour of a murdered family,[104][105] and with Leonardo DiCaprio in Clint Eastwood's biographical drama J. Edgar, playing secretary Helen Gandy.

[109] Watts starred in The Impossible (2012), a disaster drama based on the true story of María Belón and her family's experience of the 2004 Indian Ocean tsunami; she played the lead role, with her name changed to Maria Bennett.

On the film, critics concluded that Watts and Wright "give it their all, but they can't quite make Adore's trashy, absurd plot believable".

[119][120][121] The San Francisco Chronicle, praising Watts and Dillon, wrote in its review for the film that they are "formidable actors at the top of their game here [...] exhibiting a remarkable chemistry".

[123][124] James Berardinelli found the film to be a "dull, pointless" production and remarked that while Watts did a "decent job encapsulating the look and feel of Diana", her portrayal was "a two-dimensional recreation".

[133] Los Angeles Times reported a dividing reaction towards her performance, asserting that her part "put off some critics with its outrageousness", but "earned plenty of plaudits too".

[135][136][137] Watts played rebel leader Evelyn Johnson-Eaton in Insurgent (2015), the second film in The Divergent Series, which is based on Veronica Roth's best-selling young adult novel of the same name.

[143][144] Critic Richard Mowe stated the audience reaction should "give the film's creative team pause for reflection about exactly where they went so badly awry.

[157] Watts starred as "a therapist who begins to develop dangerous and intimate relationships with the people in her patients' lives" in the Netflix drama series Gypsy (also 2017), and served as one of its executive producers.

The Swans as Babe Paley, for which she received a Primetime Emmy Award for Outstanding Lead Actress in a Limited or Anthology Series or Movie nomination.

[175][176] In January 2021, it was announced that Watts was an early investor in Thirteen Lune, an e-commerce site focused on makeup, skincare, haircare and wellness products owned by people of color and ally brands.

[186] In 2011, Watts attended a charity polo match in New York City along with Australian actors Hugh Jackman and Isla Fisher, which was intended to raise money to help victims of the 2010 Haiti earthquake.

[190] In November 2018, she hosted the Worldwide Orphans 14th Annual Gala in NYC, and teamed up with McDonald's, to serve as a McHappy Day ambassador, making a special appearance and stepping behind the counter in Haberfield, Sydney.