Throughout this time and indeed throughout her career, she has regularly appeared on British TV including Murder Most English (1977), Red Shift (1977) and Deadly Game (1982), as well as two guest appearances in Doctor Who, playing roles in "Frontios" in 1984 and "The Happiness Patrol" in 1988. She starred opposite Oliver Tobias in Smuggler (1981), and Peter Ustinov in the TV film Thirteen at Dinner (1985).[4] In 1986, she appeared as the pregnant Pattie in the TV version of the Alan Ayckbourn play Seasons Greetings. In the 1990s she starred in the long-running BBC sitcom May to December[5] as Zoe Callender alongside on-screen husband Anton Rodgers, replacing Eve Matheson in the role from the series two Christmas special onwards.
In 1995, Dunlop starred in the two part Gurinder Chadha directed drama Rich Deceiver as Ellie Freeman, a Liverpudlian housewife who secretly wins the pools and uses the money to covertly help her husband's career. She also starred in the ITV series Wokenwell (1997) and the same year was in the BBC serial The Phoenix and the Carpet. She appeared in a long-running series of television adverts for Kleenex directed by Mike Leigh and played Moira Pridwell in "Something to Treasure," S4:E1 of "Hetty Wainthropp Investigates" (1998). In 2000, Dunlop joined the cast of the ITV series Where the Heart Is playing Anna Kirkwall. Since 2008, she has played the role of Brenda Walker in the ITV soap opera Emmerdale. In 2013, after Brenda was diagnosed with a brain tumour, Dunlop shaved her head especially for the part.[6] In 2024, it was announced that Dunlop would be quitting her role as Brenda.[7]