Lesson Overview
This lesson plan uses the 2025 film Last Breath as a case study to examine the true story of saturation diver Chris Lemons, whose brush with death during a North Sea diving operation highlights the intense physical and psychological demands of deep-sea commercial diving. Students will explore how saturation divers work, the technology they rely on, and the life-threatening risks they accept as part of their job. They will critically analyze how the real event is dramatized in the film and reflect on ethical questions about responsibility, risk, and safety in high-stakes work environments.
Grade Level: Upper Secondary / Post-Secondary (Ages 16+)
Subject Areas: Science, Technology, Engineering, and Mathematics (STEM), Film Studies, Occupational Health and Safety, Ethics
Background: Procedures of Saturation Diving
Directed and co-written by Alex Parkinson, Last Breath dramatizes the true story of a saturation-diving accident that took place off the coast of Scotland in 2012, and is based on Parkinson and Richard da Costa’s 2019 documentary of the same name. Saturation diving is a specialized technique used in commercial underwater work at depths that would otherwise require prohibitively long decompression times. Divers live for extended periods in a pressurized chamber aboard a vessel, where the internal pressure is maintained to match the pressure of the deep-sea worksite. From this chamber, they are transported via a sealed diving bell to the seabed. The team of three divers scheduled for a shift then descends into the water in a diving bell that is attached to the support vessel before two divers drop to the seabed while the third remains inside the bell to help ensure their safety. The submerged divers are tethered to the bell by “umbilical” cords that provide essential life support functions like breathing gas, communication, power, and heated water that let them spend long hours in the depths. Time
Breathing a carefully controlled mix of helium and oxygen, divers can work at depths exceeding 100 meters for hours at a time. Because their tissues become saturated with inert gases (hence the name “saturation diving”), they only need to undergo a single, prolonged decompression at the end of their assignment, rather than decompressing after each dive.
These procedures minimize the risk of decompression sickness (commonly known as “the bends”) but carry serious physical and mental burdens. Divers are exposed to extreme cold, disorientation, communication challenges, and the psychological strain of isolation and danger. They rely on a life-support umbilical connected to the diving bell, providing breathing gas, heat, light, and communications, and even a brief interruption can prove fatal, as it nearly did for Chris Lemons in the real-life incident explored in this film and lesson.
Learning Objectives
By the end of this lesson, students will be able to:
- Understand the principles and procedures of saturation diving.
- Analyze the real-life incident involving Chris Lemons and its portrayal in the film.
- Evaluate the ethical implications of high-risk occupations and the responsibilities of employers and society.
- Develop critical thinking skills through film analysis and research-based discussions.
Lesson Activities
Introduction and Film Viewing
1. Introduction to Saturation Diving
Begin by introducing students to the fundamentals of saturation diving. Key points to address include:
- The definition and purpose of saturation diving, especially in offshore oil and gas operations.
- An overview of the technical environment, including the use of helium-oxygen breathing gases, hyperbaric chambers, and diving bells.
- Common industrial applications include pipeline repair, rig maintenance, and deep-sea infrastructure work.
- A discussion of risks and safety protocols, including decompression procedures, life-support systems, and psychological stressors.
This introduction lays the groundwork for understanding the professional context in which the events of Last Breath occur.
2. Film Viewing: Last Breath
Screen the film Last Breath in full. While viewing, encourage students to take notes and reflect on the following:
- Key events and turning points, especially those that reveal the limitations or strengths of the divers’ equipment and procedures.
- Character decisions, particularly under duress, and how these influence outcomes.
- Depictions of technology, such as the saturation chamber, umbilical systems, and remote-operated vehicles (ROVs).
- Emotional and ethical themes, such as vulnerability, duty of care, and the psychology of survival.
This viewing should not be passive; students are expected to engage critically with the narrative and its factual underpinnings. Find the handout here.
Analysis and Discussion
3. Group Discussion
After watching the film, divide students into small groups for reflective discussion. Guide their conversations with questions such as:
- To what extent does the film accurately depict the technical and environmental realities of saturation diving?
- What human errors or decisions contributed to the crisis, and how might they have been prevented?
- How do the film’s visuals and pacing communicate the emotional gravity of the situation?
- What ethical questions emerge regarding risk, accountability, and survival?
Encourage students to cite specific scenes or dialogue to support their analyses.
4. Research Activity
Assign students to research the actual incident involving diver Chris Lemons, as well as the broader practice of saturation diving. Their inquiry should include:
- A comparison between the film and real-life accounts, identifying dramatizations or omissions.
- An investigation into how the diving industry responded to the near-fatal incident in terms of policy, training, or technology.
- Exploration of first-person interviews with Chris Lemons or others involved in deep-sea diving.
- A deeper look at how technology intersects with human decision-making in life-or-death scenarios.
Encourage the use of credible sources such as industry publications, interviews, news archives, and scientific articles.
3. Class Discussion: Ethics and Occupational Safety
Conclude with a full-class discussion centered on the broader ethical issues highlighted by the film and research. Questions to explore include:
- What moral obligations do companies have to their employees working in high-risk environments?
- How should compensation, training, and support reflect the dangers faced by deep-sea divers and others in similarly perilous professions?
- When things go wrong, how do we assess responsibility, culpability, and resilience?
Essay Question 1:
“In what ways does Last Breath illustrate the complex relationship between human decision-making and technological dependency in high-risk environments? Discuss how this relationship influenced the outcome of the Chris Lemons incident, and reflect on what it reveals about modern occupational safety practices.”
Guidance for students:
- Refer to specific scenes in the film and corroborate with factual accounts from your research.
- Consider the role of the umbilical system, remote-operated vehicles (ROVs), and life support protocols.
- Explore the tension between human intuition and procedural compliance in crisis situations.
Essay Question 2:
“To what extent should society bear moral and financial responsibility for individuals who take on extreme occupational risks, such as saturation divers? Evaluate this question in light of the ethical challenges presented in Last Breath and the real-life events that inspired it.”
Guidance for students:
- Discuss the ethical responsibilities of corporations, governments, and the public.
- Consider how the film personalizes the risks involved in such work and whether it evokes empathy or critique.
- Engage with ideas of compensation, consent, informed risk, and the value placed on different types of labor.
