Aged 47, Mrs Liddell takes up her new post with a formidable reputation. Ring round friends and enemies and the same four adjectives come up - tough, bright, knowledgeable, determined. Expect blood on the floor if, as expected after publication of the millennium review in the autumn, she takes on the Educational Institute of Scotland in an attempt to renegotiate teachers’ conditions of service.

Ask 28 leading executives from pensions companies who, within a fortnight of her taking office as Economic Secretary to the Treasury after the general election, were summoned because of a prolonged delay in compensating customers who had been mis-sold pensions. In a meeting lasting just 12 minutes, she read them a statement insisting that within a month she wanted written reports about arrangements for compensation and on progress made.

The chaps are believed to have emerged from her room visibly shaken. They had not been spoken to in such terms since they graduated to long trousers.

The executives would be most surprised to find that Mrs Liddell, ne Helen Reilly, daughter of a Coatbridge bus driver and invalid mother, was not always this forceful. She is the mouse that roared.

Although she debated in competitions at St Patrick’s High with contemporary Michael Connarty (now Labour MP for Falkirk East), when she left to study economics and politics for a general degree at Strathclyde University she admits to having been intimidated by confident A-level students from south of the border.

In her final year she sent in an application to the Scottish Trades Union Council, where she was head of the economic department from 1971-76, that was seen by her economics lecturer Sir Kenneth Alexander, who did not know that she was in his class because she had been so silent.

A veteran senior journalist also has no memory of her during the two years she spent in Westminster as an economics correspondent for the BBC a few years later.

From somewhere she found the confidence to stand - unsuccessfully - during a 1974 general election in a Fife Tory stronghold. But it seems she really found her voice when she moved out of broadcasting. Extraordinarily, at the age of only 26, she was appointed general secretary to the Scottish Labour party.

This post is generally regarded as one of the rummest in public life but during the her 11-year tenure to 1988, when Militant was making waves and the party was at its lowest ebb, the job was particularly testing. It is possible that after this hands-on experience of dealing with Trotskyite infiltrators and some of the more colourful, entrenched or corrupt members in her own party she will lose little sleep over the combined might of the teacher unions and the SNP.

This demanding period did not win her the mirror job of general secretary south of the border, but stood her in good stead when she moved to her next employer, Robert Maxwell. It is widely believed that Joe Haines, a director of Mirror Group Newspapers and former press secretary to Harold Wilson, promoted her appointment.

He wanted an effective operator and Labour loyalist dispatched to the board of the semi-autonomous Daily Record, to stop its drift towards the SNP - a role not wholly removed from that given her now in the parliamentary sphere. Plus a change.

Haines may have simultaneously performed a service to British literature in enticing her away from earning a crust by writing semi-erotic novels. Copies of Elite (now out of print) could probably change hands for a considerable sum at teachers’ union conferences, given the entertainment they provided in Labour circles at the time.

It is a light yarn of ambitious, streetwise lawyer Ann Clark, a woman of everlasting legs and auburn locks, who rose to giddy parliamentary heights thanks to the plotting of a revolutionary communist group bankrolled by an American presidential candidate bent on making Britain a satellite of the United States.

One of the sections of prose most gleefully and frequently quoted reads: “In less than 10 years she [Ann Clark] has risen explosively from middle-class political ingnue to radical left-wing lawyer to Scotland’s dominant political figure. Goddess or bitch? Both - and often at once.”

If Clark is Helen Liddell’s alter ego, then the real politician has outperformed the fictional invention. Just four years after her election in Monklands following the sudden death of her great friend and mentor John Smith, she is about to become a - perhaps the - dominant political figure in Scotland, expected to make it into the Cabinet next year as Secretary of State for Scotland when Donald Dewar becomes First Minister of the new parliament.

It comes as something of a relief to discover that this paragon positively speeding up the parliamentary ladder has other human weaknesses as well as a liking for frothy novels and expensive frocks. She tried to adopt a more refined “Kailvinside” pronunciation of her name and during her brief spell as a novelist in London Helen Liddell metamorphosed into someone who sounded like Helen Liddelle.

The mild affectation travelled with her when she was recruited to MGN. Alas, pretentiousness does not travel so well in west of Scotland political circles. When an ever so English executive of MGN presented “Helen Liddelle” at a Scottish Labour party conference, a heckler from the back of the room enquired: “Is that Helen ‘Liddelle’ from ‘Drumchapelle’?” There followed a spontaneous explosion of laughter from the assembly, but from the lady concerned only a sweeping glare trying to identify the caller.

It was often said by her enemies at the Record that she was Robert Maxwell’s eyes and ears there. Only after he died, did Mirror Group employees discover what a control freak Maxwell was, with much of MGN bugged by a high-tech security expert, even the offices of the two sons who worked for him. Her supporters say enemies were thick on the ground when Liddell first joined the Record, largely because she was female, Labour and appointed by London.

Present-day enemies say she is soiled goods, given the senior executive position she held under the Bouncing Czech. Her defenders say this is an arbitrary claim since no aspersions are cast at the Prime Minister’s press secretary Alastair Campbell, the former political editor of the Daily Mirror who was sufficiently upset on the day Maxwell died to physically attack a Guardian journalist who made fun of the event. At the time of employment, staff had no inkling that Maxwell was so very different from other press barons.

One insider says of this period: “Helen has never been credited as one of a handful of people who stood up to Maxwell. She had many rows with him and a few weeks before his death he wanted to sack her because she was pressing him hard on machines for the Record. The rest fawned on him. She wasn’t like the bloody poodles outside his office.”

Critics say Liddell is also tarnished by her failure to dissociate herself from the scandal-ridden Monklands council until the last days of the bitter Airdrie by-election which she won by a relatively modest margin. SNP opponent Kay Ulrich is naturally among her fiercest critics, claiming Liddell “fought a press campaign rather than a people campaign”.

She was rarely seen knocking on individual house doors. Her supporters say that prioritising communication with thousands of people at a time is simply effective time management, the skilled art of the working mother.

One suspects that back at the comfortable home in Langbank between Glasgow and Greenock, husband Alistair, a manager with Polaroid, daughter Clare, aged 13 and son Paul, an 18-year-old student of philosophy, politics and economics at Glasgow University, still manage to see more of the paid housekeeper than they do of hard-working Helen.

A Thatcher-like capacity to perform routinely on less than five hours sleep a night frees what time she can for family and for the hobbies revealed this week by the Scottish Office press office. There is no mention of her accomplishments as a jazz singer, which came to light at a Labour party conference reception, but the list includes cooking, hillwalking, music and, um, writing.

Ominously, Elite is described as “her first novel”.