As the lights dim and an eerie drumbeat starts, two figures take centre stage, reaching out wordlessly in unison again and again, in a rhythmic, hypnotic motion. Back and forth, back and forth, their fingers fluttering at first as the girl standing copies the demanding, grasping gesture of the one sitting beside her.
A voice breaks over the quiet as two more figures from a group encircling the space begin to address each other across the room in turn, as if corresponding by letter.
"My dearest Lara, I have not seen you since we were separated in Ghana . The constant lashings . sometimes I feel like I'm slowly dying here. A month upon that ship felt like a lifetime in Lucifer's grasp."
As the dialogue continues, the movement of the two silent girls, trapped in the middle of the room, suddenly alters as the one standing steps forward alone, spinning tentatively across the floor away from her seated master as she finally breaks free.
This dramatisation of Scotland's role in the slave trade by a group of students at Crieff High is the result of less than two hours of brainstorming and experimentation.
The 14 fourth- and fifth-year drama students are taking part in one of the latest workshops run by the National Theatre of Scotland. It is designed to show students and teachers the creative processes behind the company's award-winning play about the war in Iraq, Black Watch.
The renowned production is back in Glasgow for the fourth time in what is expected to be another sell-out run in the city. It has now been performed to thousands of people, not just at home but abroad with continuing tours across four continents, garnering 22 accolades along the way.
Even those who have yet to see Black Watch in Scotland generally know that Fife writer Gregory Burke based it on interviews with soldiers from the regiment. He spent hours during Sunday afternoon drinking sessions in the pub, listening to their banter and asking about their often harrowing experiences in the controversial conflict.
Less well known is the way the play came about and how Burke's writing was drawn together with the choreography devised by associate director of movement, Steven Hoggett.
Gareth Nicholls, a freelance theatre director who has been leading Black Watch workshops since the play premiered in Edinburgh in 2006, tells the Crieff students: "Gregory Burke was given an assignment to keep an eye on the Iraq War in the news, to read the papers and follow what was happening.
"He actually wrote independently and Steven (Hoggett) had already started developing movement work with the actors, so there was a lot of back and forth as they worked out how the text and the music and movement fitted together.
"We're giving you an assignment too and we're going to brainstorm and try things out together to see what works and what doesn't."
The idea for the slavery theme is one of three which the students put forward at the start of the workshop this morning, after being asked beforehand to work in teams on researching newsworthy topics for a new play.
Selling their proposals is a key part of the creative process and students give a two-minute pitch to the whole group, outlining the dramatic possibilities of their choice before they all vote on which is best.
The other two suggestions are the election of the new Pope, Francis I, against the background of continuing rivalry between Argentina and Britain over the Falklands, and the enduring scandal of health chiefs fiddling NHS waiting lists to prioritise government targets over patient care.
Slavery is the most unusual topic, coming from the release last month of previously unseen records detailing massive payouts to British merchants in compensation for what was termed "loss of property", when slavery was abolished in the colonies in the 19th century.
The group presents a range of hard-hitting statistics gleaned from modern news reports, including the fact that the then British government spent 40 per cent of its budget on compensation for slave owners, including many Scots.
"We think there is good dramatic potential linking with historical facts for interesting characters to show the light and dark side of the slave trade, and themes of crime, materialism and greed, which are issues in Scotland today too," one of the students says.
Their pitch wins by a landslide and Mr Nicholls divides the whole group into two, with students who prefer creative writing focusing on texts while the rest work on movement routines.
The latter group decides to base an ensemble piece on the repetitive movements of slaves working on a ship. Each student finds a space in the drama studio and starts improvising four key poses. Two boys crouch with heads bowed while a girl pulls an imaginary rope as they build up a routine.
In one corner of the room, two girls work on the slave-and-master duet, trying different movements of their arms to represent the idea of control.
Mairi Henderson, 16, playing the slave, says: "It's quite challenging but good fun. It does make you think about what it must have been like (to be a slave), that sense of vulnerability.
"I've never done anything like this workshop before with a theatre company. It's really good because they are giving us an insight into the techniques which they used for Black Watch, which obviously worked really well because it is so good. I have seen it and I really loved it."
In another corner, near the door of the drama studio, Marianne Lamb and Jemma Jackson, both 15, are standing typing text quietly into their mobile phones (as pictured below).
Marianne says: "We're sisters who were separated by slavery, so we're writing letters to each other which we will read as a dialogue, and then it will go into flashbacks.
"We have studied slavery in Standard grade for a history topic, so we know a bit about it.
"Neither of us has seen Black Watch, but the workshop is really good. I thought I would be much more panicky when we had to do our pitch, but I was quite calm."
Mr Nicholls has suggested researching slave songs too, and nearby Sheilanne Smith, 16, is using a computer to try to find some online.
She says: "I've found some songs of freedom and there's one called Oh Freedom that I like. It's quite powerful with the repetition of the word (freedom) and the way the song has been structured.
"I love Black Watch and it's really interesting as a play, because it is something that affects so many people and it was devised so differently. They actually interviewed soldiers instead of just writing somewhere alone at a computer, which - for a topic like the war - made such a difference."
When the two groups come together to try combining their ideas after such a short space of time, it looks impressive, though drama teacher Graham Leadbitter says that it is the kind of speed he expects of students.
Mr Leadbitter believes the benefits of workshops can be pretty immediate for them at this stage, saying: "It's rare to be able to see a production which you are studying and to be able to work with the theatre company.
"This is really good experience for students. In a few weeks' time, they might have a question in their exam like `Think of a production that you have seen recently. How do you think that production was realised?' They will be able to use this experience today to answer that."
Mr Leadbitter, who is also an NTS "champion", volunteering to promote theatre in his community, adds: "I have a thing of always contacting theatres to see what they have got on each year, because that may influence my decision on which texts we study. Workshops, question and answer sessions and backstage visits are all really useful."
Meanwhile, Mr Nicholls believes that the workshops have another important message for students.
"It's about empowering them, setting them creative tasks based on reacting to what they are interested in, which is exciting for us and for them, I think.
"But it's also about instilling the idea of giving things a go, which is very important in the devising process, instead of just sitting around talking about things. You have to take creative risks and it's all right if it does not always work.
"I think it's nice for them to know that these people at the top of the game fail too sometimes, and that's OK."
WRITE ON: BURKE BELIEVES THAT WE ARE ALL STORYTELLERS
As no-show excuses go, being called up by Broadway is at least impressive.
And while planned Qamp;A sessions with Black Watch director John Tiffany and associate movement director Steven Hoggett are cancelled at the last minute as a result, the seven drama teachers at this CPD session on the award-winning text don't seem unhappy.
That may be because they can still submit questions via email to be answered in a DVD, which will be posted to them.
But it's probably largely on account of the presence of the play's writer, Gregory Burke, who won the 2008 Writers' Guild Award for Black Watch in the Best New Play category, and is still very much here.
As he explains how he wrote the play, it's clear that he is a prime example of his belief that we are "all storytellers" and everyone has family tales like one from his grandfather about army recruitment, which he says inspired a key scene in Black Watch.
He is also frank about having no idea if the show would work, much less that it would become a global success.
Silence descends briefly as the teachers write their own personal anecdotes before recounting them to the group, sitting in a circle in a room at the National Theatre of Scotland's administrative base in Glasgow.
Christine Wheatley, drama teacher at Glasgow's Hillpark Secondary, who recalls a common theme of scandal surrounding Catholics marrying Protestants, says afterwards: "I felt a bit under pressure, so it's helped me to know how it feels to be a student put in that situation. It's also useful to see what can be developed from any of these stories."
Black Watch returns to Scotland at the SECC in Glasgow from 28 March to 13 April. www.nationaltheatrescotland.com. Photo: Actor Scott Fletcher as soldier Kenzie in the play Black Watch. Photo credit: National Theatre of ScotlandManuel Harlan
Photo: Actor Scott Fletcher as soldier Kenzie in the play Black Watch. Photo credit: National Theatre of ScotlandManuel Harlan