Sheena Shirley Easton (née Orr; born 27 April 1959) is a Scottish singer and actress who achieved recognition in an episode of the reality television series The Big Time: Pop Singer, which recorded her attempts to gain a record deal and her eventual signing with the EMI label. Her first two singles, "Modern Girl" and "9 to 5", both entered the top ten of the UK singles chart simultaneously. She became one of the most successful British female recording artists of the 1980s.

Easton became the first and only recording artist in Billboard history to have a top-five hit on each of Billboard's primary singles charts: "9 to 5" (Pop and Adult Contemporary), "We've Got Tonight" with Kenny Rogers (Country and Adult Contemporary) and "Sugar Walls" (R&B and Dance). Her discography includes fifteen studio albums, fifty-five singles and twenty consecutive US singles, including fifteen top forty hits, seven top tens and one number-one single on the Billboard Hot 100. Easton has combined record sales of over 20 million worldwide. In 1981, Easton recorded "For Your Eyes Only" as the theme song for the James Bond film.

A six-time Grammy Award nominee, Easton is a two-time Grammy Award winner – Best New Artist for 1981 and Best Mexican-American Performance in 1985 for her duet with Mexican singer Luis Miguel on the 1984 single "Me Gustas Tal Como Eres".

Sheena Shirley Orr was born on 27 April 1959, at Bellshill Maternity Hospital in Lanarkshire, Scotland, the youngest of six children of Annie and steel mill labourer Alex Orr. She has two brothers, Robert and Alex, and three sisters, Marilyn, Anessa, and Morag. Her earliest-known public performance as a singer was in 1964 at the age of five, when she sang "Early One Morning" for her uncle and aunt and various relatives at the couple's 25th wedding anniversary celebration.

Easton's father died in 1969 and her mother had to support the family. According to Easton's website, despite her mother's heavy workload she was always available for her children: "Sheena always speaks very highly of her mum and the wonderful job she did in bringing up her and her siblings, including teaching them all to read at home before they were even enrolled in school." Easton did not consider a singing career until she saw the movie The Way We Were, with Barbra Streisand. Streisand's singing over the opening credits "overtook" the young girl and convinced her that what she wanted most was to be a singer and to have the same effect on others. Her top grades in school earned her a scholarship to attend the Royal Scottish Academy of Music and Drama in Glasgow, where she trained from 1975 to 1979 as a speech and drama teacher by day, while singing with a band called "Something Else" by night at local clubs. She chose to study teaching rather than performing, because it was a course of study that would let her perfect her craft as a singer.

In 1979, she married Sandi Easton, the first of her four husbands. They divorced after eight months, but Sheena decided to keep the surname Easton. That year, one of her tutors coaxed her into auditioning for Esther Rantzen, producer of the BBC programme The Big Time. Rantzen was planning a documentary film to chronicle a relative unknown's rise to pop-music stardom. Easton was selected as the subject for the programme; EMI executives awarded her a contract, and Christopher Neil was assigned as her recording producer. Deke Arlon became her first manager, and Easton spent much of 1980 being followed by camera crews, who filmed her throughout the process of her audition through to making her first EMI single, "Modern Girl". In the course of the filming, she met and sang for Dorothy Squires, Dusty Springfield and Lulu, whose manager Marion Massey told her that she saw Easton as a potential movie or TV star with her own series, but not as a pop singer for the 1980s as she lacked "rugged individuality".

The encounter with Massey (then Marion London), at which Lulu was present, was filmed and included in the broadcast, at which time Massey was not entirely incorrect, as "Modern Girl" flopped on its release, peaking at number 56 in just three weeks on the UK Singles Chart in April 1980. However, the conversation centered around image, with Lulu politely interjecting to say, "She's such a good-looking girl. You could actually do a lot with her." Once the programme aired in August 1980, "Modern Girl" was reissued and the track and its follow up "Nine to Five" both leapt into the top 10, seemingly disproving Massey's prediction, although Easton's look was noticeably different after the filmed conversation. A revised and extended version of this episode of The Big Time, broadcast in 1981, concluded with news of Easton's breaking into the American market.

Easton's first single, the disco-tinged soft-synth-pop tune, "Modern Girl", was released in the UK before The Big Time aired, reaching number 56. At the end of the show, Easton was still unsure of her future as a singer. The question was resolved soon after the show aired, when her second single, "9 to 5", reached number 3 on the UK Singles Chart and was certified a Gold single in 1980. "Modern Girl" re-entered the chart subsequently and climbed into the top 10, being certified a Silver single, and Easton found herself with two songs in the UK top 10 simultaneously.