YOU are a commissioning editor in television drama. Which of the following scripts would you choose for a gritty, realistic series about a failing secondary school?
Script A follows the fortunes of a mid-career headteacher who is moved from a successful secondary to rescue one that has been "named and shamed".
He battles with the local authority, struggles with recalcitrant staff and duels with disruptive pupils. There are no quick fixes and, one year on, this energetic, street-wise head is still struggling to improve his school.
Script B's heroine is a softly-spoken grandmother with a title and a penchant for pearls and high heels. She is ensconced in retirement when invited to take over at a failing school where the former headteacher has been murdered.
In under four months, she transforms the school, improving teaching, learning, behaviour and attendance. Inspectors praise her students as "delightful".
Script A sounds more credible. As for B, it is surely just too far-fetched: not even the most super of "super heads" could achieve so much change so quickly.
Yet A is fiction and B is fact. The former is the basis for the BBC series Hope amp; Glory, starring Lenny Henry.
Script B is playing for real at St George's in Westminster, where Philip Lawrence was fatally stabbed just outside the school gates in December 1995.
Two years ago, St George's was judged to be "failing" by the Office for Standards in Education. This February a further violent incident brought the departure of its then head and temporary closure by the LEA. Permanent closure loomed.
Cue the dramatic arrival of Lady Marie Stubbs. Six months retired and enjoying time with her grandchildren, this "headmistress" (her favoured term) hardly seemed a likely candidate for the toughest job in education.
Yet she has achieved an extraordinary transformation which promises to remove the school from special measures. OFSTED says the "learning environment has improved significantly" and the school is now "a more stimulating and vibrant environment in which to learn".
So how did Lady Stubbs do it? Does she have that mystical quality that super heads seem to need?
I visited St George's recetly and saw clues to these questions. The contrast with Lenny Henry's headteacher was instructive.
While his character attempts to be cool, casual and jocular with pupils and staff, Lady Stubbs is a stickler for old-fashioned qualities, such as neatness, politeness and punctuality. She is 1950s Ealing film studios to his kitchen-sink drama.
As I followed her around the corridors, her radar picked out one girl wearing a non-regulation shirt. She was quietly, but firmly, told to change it. Two boys were instructed to wait a moment to allow the school's visitors to pass through the door first.
She is, in her own words, "an iron fist in an iron glove" and someone who "likes to win". But the image of a tough traditionalist, while partly true, is not the complete picture.
For example, she has not excluded a single pupil. The discipline is quiet and calm and is achieved more by promise of rewards than threats of reprisals.
She believes in consultation. I listened as Year 7 students discussed how to introduce next September's new intake to the school. Student councils decide many matters, including which visiting speakers to invite and what the rewards should be for students who meet their targets.
There are some other nice touches too: the freshly-painted brightly-coloured walls to create a sense of vitality and newness, the calming classical music piped throughout the school at break-times, and the "silent radio" display system which celebrates daily achievements at the school.
But you really notice her extraordinary air of authority. Meeting her reminded me of being in the presence of Lady Thatcher: love her or loathe her, you couldn't ignore her. If this quality could be bottled, the National College for School Leadership should prescribe it to all aspiring heads.
Like most of the "superheads" I have met, Lady Stubbs vehemently rejects the label. She doesn't get a "superhead" salary.
But the quality she, and some other heads I have seen in action, warrant the "super" prefix. Few have that special quality: those who do need not be so modest and those who don't could profit by observing those who do.
Mike Baker is the BBC's education correspondent.