Briony McRoberts: Versatile actress and star of 'High Road'

The actress Briony McRoberts spent two decades taking character roles on television before making her biggest impact as the super-bitch Sam Hagen in Take the High Road, the Scottish soap opera screened nationally by ITV.

The glamorous Sam arrived in the fictional village of Glendarroch in 1991 as a dynamic business executive and eventually bought the estate, becoming the lady laird.

In 1994, the serial's title was shortened to High Road, following the vogue of the times – five years earlier, Emmerdale Farm had become Emmerdale. The Scottish Television soap also followed its Yorkshire counterpart in featuring more raunchy storylines.

As the glamorous Sam, who could be thoroughly ruthless in her business dealings, McRoberts brought steamy passion to the community on the banks of Loch Lomond. The character had a string of affairs – starting with Davie Sneddon (Derek Lord), the local "JR", because he had information useful to her business interests – and she even bedded a teenage boy (played by Gary Hollywood, above).

In 2000, when McRoberts left the serial, Sam hit the bottle after being jilted by a lover, then disappeared. Early the following year, news reached Glendarroch that her body had been found on a rubbish tip and she had lived her last days destitute. The actress made only a handful of television appearances after leaving High Road.

Briony McRoberts was born in Hertfordshire in 1957 but, aged six, moved to Richmond-upon-Thames following the death of her mother and her father's remarriage.

As a child, she studied drama at the Professional Children's School, in Teddington. This led to her screen debut, uncredited, at the age of 12 with a small role in the 1969 film fantasy Captain Nemo and the Underwater City, directed by James Hill, who had made Born Free three years earlier and had a particular talent for getting the best out of child actors.

As an adult, McRoberts made her first television appearance as Anna, one of the children fostered by the failed romantic played by Ian Carmichael in the sitcom Bachelor Father (1970-71), and other roles soon followed.

She was seen as Wendy Darling in a live-action television musical version of Peter Pan (1976), starring Mia Farrow and Danny Kaye; as Esther Bronte in The Crezz (1976), with Joss Ackland and Elspet Gray as her parents; as Charlotte, a student, in the final series of the sitcom Sink or Swim (1982); and as Caroline, secretary to the Whitehall-based spycatcher played by Alec McCowen, in Mr Palfrey of Westminster (1984-85). In 1990, McRoberts briefly acted Janine Butcher's counsellor, Carol Nickleson, in EastEnders.

She was also in the film The Pink Panther Strikes Again (1976) as the glamorous Margo Fassbender, who is kidnapped with her physicist father by Chief Inspector Dreyfus (Herbert Lom), out of a psychiatric hospital and intent on killing Clouseau (Peter Sellers), who has driven him to the edge.

McRoberts met the actor David Robb when they were both in a disastrous 1975 production of the William Douglas-Home play Betsy at the Yvonne Arnaud Theatre, Guildford. They married three years later.

On the West End stage, she acted at the Shaftesbury Theatre in the musicals Maggie (1978), alongside Anna Neagle, and Peter Pan (1980), again as Wendy Darling, then appeared at the Aldwych in Charley's Aunt (1983). Her last television appearance was in a 2005 episode of The Bill.

McRoberts's final acting role was alongside her husband and actress friend Joanna Lumley in a production of Walter Scott's epic poem "The Lay of the Last Minstrel" at the Borders Book Festival in June.

She and Robb – who played Dr Clarkson, the Crawley family GP, in Downton Abbey and has been a volunteer for the Samaritans for a quarter of a century – ran the Edinburgh marathon every year from 2004 to raise money for Leukaemia Research.

McRoberts was killed after being hit by a London underground train. Police said there were no suspicious circumstances and her agent stated that it was believed the actress had committed suicide.

Anthony Hayward

Briony McRoberts, actress: born Welwyn Garden City, Hertfordshire 10 February 1957; married 1978 David Robb; died London 17 July 2013.