The episode has been entirely improvised (Picture: BBC)

This Saturday’s episode of Casualty will be a special one. As well as it highlighting the strain NHS paramedics are currently under – it will be entirely improvised.

Focusing on Jan (Di Botcher), Iain (Michael Stevenson), Sah (Arin Smethurst) and Teddy (Milo Clarke), the episode will be set across four days and will show the pressure and obstacles they are faced with on busy shifts.

It has been Casualty’s proud tradition over its 36-year history to reflect the difficult realities front-line health care workers are faced with, and this episode continues that tradition as it sheds light on the effect ambulance queues has on the hospital, its patients, and the front-line medical staff themselves.

As Jan returns from her holiday, she has a spring in her step, but her mood drastically changes when she makes a mistake during her shift, which results in a terrible accident.

Elsewhere, Teddy’s confidence is undermined and Iain and Sah both battle intensely stressful situations.

Jon Sen, Executive Producer of Casualty for BBC Studios said: ‘Casualty is at its best when it tells stories that truly chime with the real experience of working medics in the NHS. The ambition behind the ep was to tell a story that gets as close as possible to what it is like to stand in the shoes of paramedics up and down the country.

After our extensive research, using improvisation techniques to capture the truth of the world seemed only natural. We want people to come away having a greater respect for the work paramedics do and a true appreciation of the challenges they face.’

Steve Hughes, Director of the episode added: ‘The actors improvised all their dialogue and we shot everything like a documentary to give it a grounded, naturalistic feel. It was vital to make this episode feel as authentic as possible to highlight the challenges paramedics, and the NHS as a whole, face on a daily basis.

‘It was scary for the actors at first, like they were walking a tightrope without a net, but it was also freeing and exciting to be able to use their own voices and, even though most of them hadn’t done anything like this before, they all rose to the challenge and I’m so proud of what we achieved.’

The episode will air this Saturday.