She provided the voice of Sophie in the English-language version of Howl's Moving Castle (2004), and starred in Scream 3 (2000), Match Point (2005), The Pink Panther (2006), The Pink Panther 2 (2009), Lars and the Real Girl (2007), Chaos Theory (2008), Harry Brown (2009), Shutter Island (2010), Cars 2 (2011), Hugo (2011), Mary Poppins Returns (2018), and Relic (2020).

While acting in a student production, she was spotted by a producer who later cast her as the lead in a television adaptation of Catherine Cookson's The Glass Virgin (1995).

[citation needed] In 1996, Mortimer appeared in her first feature film opposite Val Kilmer in The Ghost and the Darkness, and in the coming-of-age story, The Last of the High Kings.

In 1999, she played three roles: she was the "Perfect Girl" dropped by Hugh Grant in Notting Hill; Esther in the television miniseries Noah's Ark, and the actress Angelina in Scream 3.

In 2000, Mortimer was cast as Katherine in Kenneth Branagh's musical adaptation of Love's Labour's Lost, where she met actor and future husband Alessandro Nivola.

[17][18]In 2003, Mortimer appeared in Stephen Fry's British drama, Bright Young Things, based on the 1930 novel Vile Bodies by Evelyn Waugh.

[22] In 2004, Mortimer played the lead role in the drama Dear Frankie, about a young mother whose love for her son prompts her to plan a deception to protect him from the truth about his father.

[24] In an interview with critic Roger Ebert, Mortimer said, "I seem to find characters who are held back and guarded, physically and mentally.

[25] In 2005, she played Chloe Wilton, the oblivious spouse of Jonathan Rhys Meyers's adulterer in Woody Allen's Match Point.

Writing for The Guardian, Peter Bradshaw opined that Mortimer's performance was "perfectly plausible",[26] and CNN's critic complimented the entire cast.

[29] In 2007, she had a role in the comedy drama Lars and the Real Girl as Karin, the supportive sister-in-law of Ryan Gosling's title character.

Critical reception was mostly mixed,[32] and Ruthe Stein of San Francisco Chronicle thought Mortimer and Reynolds lacked chemistry.

The film gained fair reviews,[36] and The Telegraph critic wrote, "Emily Mortimer is impressive as a jittery, unlikable attorney".

[38] In the last three episodes of the first season of 30 Rock, she played Phoebe, the mysterious love interest of Alec Baldwin's character, Jack Donaghy.

[40] Betsy Sharkey of Los Angeles Times wrote of Mortimer's performance: "Her clinical coolness plays well off of Caine's controlled heat.

Several critics thought Shutter Island was unexciting, and that Mortimer and her fellow actors were not utilised to their full potential.

[52][53] In January 2013, it was announced that Mortimer would be co-creating and starring in the comedy series Doll & Em for Sky Living, along with her longtime friend, actress and comedian Dolly Wells.

Playing the mother Sarah Ford, Mortimer garnered praise for her lively performance,[56] while one critic thought she was miscast.

Adapted from the 1978 novel of the same title by Penelope Fitzgerald, Mortimer played Florence Green, who opens a bookshop despite local opposition.

Writing for Chicago Reader, Andrea Gronvall noted, "The ever-winsome Emily Mortimer glows as a struggling widow",[60] and Variety magazine opined that it was "A fine, sensitive leading turn" for the actor.

It co-stars Grace Van Patten as Lilian, a young woman who moves in with her father's friend, a reclusive novelist called Julia Price (Mortimer).

[74] In 2021, Mortimer wrote, directed, and starred in the miniseries The Pursuit of Love,[75] which earned her a BAFTA TV nomination for Best Supporting Actress.