McCallum appeared in Glasgow drama
Just Another Saturday in 1975. She then gained her first major soap role in
Garnock Way playing Jean Ross from 1976 to 1979.
Garnock Way was axed to be replaced by
Take the High Road, which was first aired on 19 February 1980 with McCallum taking one of the lead roles as village storekeeper Isabel Blair through the programme's full run from 1980 to 2003. Series creator
Don Houghton praised McCallum and her co-star
Marjorie Thomson for their clarity as speakers of the
Scots dialect, an essential attribute of their respective roles in the programme. McCallum was awarded the
MBE for her services to drama in the 1992 New Year Honours. Other notable roles include playing Dolly in the television version of
Tony Roper's The Steamie and guest appearances in programmes such as
Rebus,
Still Game and
New Tricks. She has also worked on radio. In 2006, she joined the cast of the
BBC Scotland soap opera
River City as
Liz Buchanan, then later Hamilton. In 2015, she appeared as Mrs Gaffney in
The Legend of Barney Thomson. After 12 years in
River City, McCallum retired from the role in May 2018. ==Theatre==