In the mid-1970s, Mirren enjoyed a breakthrough with her acclaimed performance as Nina in a West End revival of Chekhov's "The Seagull.” That role allowed her to combine her intelligence with her sensuality, something which has come to be her hallmark. The actress managed to bring a measure of grace to her part as the most promiscuous woman in Rome in the controversial "Caligula" (1979), which in retrospect didn’t seem as daring as it did at the time.

Mirren came into her own as a film actor beginning with her strong turn as the lover of a gangster (Bob Hoskins) in "The Long Good Friday" (1979). She lent an appropriately seductive air to the evil Morgana in "Excalibur" (1981), John Boorman's revisionist take on the Arthurian legend and then returned to her stage roots for a series of TV appearances in Shakespeare plays. With "Cal" (1984), the actress hit new heights, turning in a memorable performance as the widow of a British soldier who unwittingly falls in love with the Irishman (John Lynch) responsible for his death. Although she earned the Cannes Film Festival prize as the year's best actress, she did not garner the same attention when the film was released in the United States. She got to draw on her heritage when she was cast as a Russian astronaut in "2010" (1984) and as Mikhail Baryshnikov's lover in "White Nights" (1985). (The latter film introduced Mirren to director Taylor Hackford who became her off-screen companion and later her husband.) Mirren was formidable as the wife who follows her husband to Central America in "The Mosquito Coast" (1986), but few saw the film in its theatrical release. She was also excellent as a painter who catches the eye of spy Ben Kingsley in "Pascali's Island" (1988). Mirren rounded out the decade with a fine turn as the long-suffering spouse of an abusive criminal (Michael Gambon) in "The Cook, the Thief, His Wife and Her Lover" (1989).

Mirren found her signature role in 1990 when she was cast as Detective Inspector Jane Tennison in the superb "Prime Suspect.” Tennison was an inspired creation: a middle-aged woman trying – and mostly succeeding – to make it in a man's world. The first series proved to popular that Tennison was revived for a total of six (to date). Mirren earned three consecutive BAFTA Awards (1991-93) and four (thus far) Emmy nominations for the part, including a 1996 win for Outstanding Lead Actress in a Miniseries or a Special.

During the run of "Prime Suspect,” Mirren found herself in demand and she was cast as the loyal queen to the increasingly irascible monarch (Nigel Hawthorne) in the film "The Madness of King George" (1994). Her stellar performance netted her a Best Supporting Actress Oscar nomination and a second citation from the Cannes Film Festival. She remained regal for "Royal Deceit/Prince of Jutland" (also 1994), a drama which purported to tell the "real" story of Hamlet. Moving into production, Mirren served as an associate producer on "Some Mother's Sons" (1996), in which she starred as the parent of a man arrested and imprisoned for alleged ties to the IRA. She did the same double duty (associate producer and star) on the 1997 TV drama "Painted Lady,” playing a faded rock singer who becomes an amateur sleuth. Rounding out the century, Mirren earned a second Emmy playing the titular philosopher "The Passion of Ayn Rand" (Showtime, 1999) and brought a humanity to the titular harridan educator in "Teaching Mrs. Tingle" (1999).

On the big screen, she played a dotty horticulturist in the genial comedy "Greenfingers" (2000) and made her directing debut with "Happy Birthday,” a segment of Showtime's "Directed By" series called "On the Edge" in 2001. Mirren had two of her best screen roles in 2001, playing the officious housekeeper of an English estate in the Robert Altman-directed "Gosford Park" and as the widow who refuses to accompany her deceased husband's friends as they go to spread his ashes in "Last Orders.” The former brought the actress her second Oscar nomination as Best Supporting Actress.

Although "Georgetown," a well-regarded pilot for CBS television in which she played a shrewd Washington hostess and newspaper mogul (described as a cross between publisher Katharine Graham and party hostess Pamela Harriman), did not make the cut for the 2002 season, the actress enjoyed two standout turns in a pair of particularly high-quality television productions, "Door to Door" (2002), playing the mother of the mentally challenged salesman played by star and screenwriter William H. Macy, and "The Roman Spring of Mrs. Stone" (2003), playing the failing star whose life is upended by the death of her husband while vacationing in Italy in the telepic inspired by the Tennessee Williams novella. The projects earned her a pair of 2003 Emmy nominations – for Outstanding Supporting Actress in a Miniseries or a Movie and Outstanding Lead Actress in a Miniseries or a Movie, respectively – as well as back-to-back Screen Actors Guild Award and Golden Globe nominations as Best Performance by an Actress in a Mini-Series or a Motion Picture Made for Television in 2003 and 2004. She was also named a Dame of the British Empire in the Queen's Birthday Honours in June of 2003.

Mirren then starred among the ensemble of the sprightly British comedy "Calendar Girls" (2003), inspired by the true story of the Rylstone Women's Institute in North Yorkshire, a group of everyday women who decide to pose nude for their annual calendar to raise funds for Leukemia research, inspiring sales that outdid even the sexiest of celebrity calendars. The performance earned Mirren a Golden Globe nomination for Best Performance by an Actress in a Motion Picture Musical or Comedy. Mirren next appeared in a small but scene-stealing role as Dominique, queenly head of a Manhattan modeling agency where Kate Hudson works in "Raising Helen" (2004).

Mirren has continued to divide her time between the stage and screen, making her Broadway debut in "A Month in the Country" in 1995 and returned to the London theater in "Collected Stories" (1999) and "Orpheus Descending" (2000). She returned to Broadway opposite Ian McKellen in "Dance of Death" in 2001 and was nominated for a Tony award for Best Performance by a Leading Actress in a Play for her role in 2002. She was nominated for a Laurence Olivier Theatre Award in 2001 for Best Actress in her performance of "Orpheus Descending" at the Donmar Warehouse, and her London performance on the National's Lyttelton stage in 2003-2004 as the murderous Christine Mannon in "Mourning Becomes Electra" earned her a nomination for another Olivier award. She returned to the big screen in “The Clearing” (2004), playing the victimized wife of a wealthy executive (Robert Redford) kidnapped by a disgruntled employee (Willem Dafoe), then voiced the supercomputer Deep Thought in the long-awaited, but deeply unsatisfying adaptation of Douglas Adams’ comic sci-fi adventure, “The Hitchhiker’s Guide to the Galaxy” (2005).

After a turn as an assassin in the dismal noir thriller “Shadowboxer” (2005), Mirren once again displayed her extraordinary poise and talent in “The Queen” (2006), movingly portraying Queen Elizabeth II in a quiet, guarded performance the earned the actress legitimate Oscar buzz after its September 2006 release. Set during the crisis that gripped England after the untimely death of Diana, “The Queen” pits Elizabeth against the newly elected Prime Minister Tony Blair (Michael Sheen), who rightly believes that the Queen’s isolation and refusal to publicly mourn the People’s Princess might threaten to shake up the monarchy, even though it is technically proper for the Royal Family to mourn in private. Ultimately torn between responsibility and emotion, custom and action, the Queen battles Blair both publicly and privately, along the way realizing that she has lost touch with her subjects, and that doing the proper thing is not necessarily the same as doing the right thing.

In 2006, Mirren perhaps had her best year award-wise, earning critical adulation and recognition across the board for her performance in “The Queen.” She won Best Actress awards from several film and critic associations, including the San Francisco Film Critics Circle, the Boston Society of Film Critics, the Los Angeles Film Critics Association and the National Board of Review, then earned a nod for a Golden Globe Award for Best Actress – Motion Picture. In an ironic turn, Mirren was also nominated for a Golden Globe for her performance in “Elizabeth I” (HBO, 2006), a widely honored miniseries—it won nine Emmy Awards, including for Outstanding Miniseries—that depicted the public and personal life of the Virgin Queen during the second half of her rule, focusing on how she lived in and survived a male-dominated world.

A third Golden Globe nomination for 2006 was bestowed upon Mirren for her performance in Prime Suspect: The Final Act” (PBS, 2006), the seventh addition to the long-running “Masterpiece Theatre” series that saw a tired Detective Superintendent Jane Tennison on the verge of retirement having to contend with the grisly murder of a pregnant 14-year-old girl. Mirren took two out of three at the Golden Globes, winning for her performances in “Elizabeth I” and “The Queen,” making her the odds-on favorite for an Oscar win in the Best Actress category. Mirren took the first step when she was nominated by the Academy for Best Actress, joining fellow Brits Judi Dench and Kate Winslet, as well as Penelope Cruz and Meryl Streep. As many had predicted, virtually across the board, Mirren won the prestigious award for her affecting work as "The Queen." On the television side, Mirren kept the award train rolling with an Emmy for Outstanding Lead Actress in a Miniseries or Movie for her performance in “Prime Suspect.”