Apple TV+In Severance Season 2 Episode 10, Gemma finally sees what’s inside the Cold Harbor room on the Testing Floor – and she’s forced to participate in an Efficacy Test.
Cast your mind back to Episode 7. Under Dr. Mauer’s constant supervision, Gemma put her Innie(s) through the wringer in various rooms, each individually severed; one spends their life at the dentist, while another does nothing but write thank you letters at Christmas.
There was only one room left: Cold Harbor, the same name as the file Mark was working on upstairs. In Episode 10, he completes it – and it sets off a chain reaction that changes everything.
What happens inside that room is the key to understanding what’s really going on in Severance; in an instant, Kier’s “grand agendum” is revealed.
What is an Efficacy Test?
Apple TV+An Efficacy Test assesses the effectiveness and reliability of a product; in Severance’s case, it’s the extent to which Gemma’s chip insulates her from her own trauma.
As Wirral Sensory Services explains, “efficacy testing involves a series of experiments and trials designed to measure whether a product performs its intended function effectively.
“It is an essential component in the development and evaluation of products that claim to have specific beneficial effects.
“It’s not just about meeting the minimum standards; efficacy testing also plays a significant role in product development and improvement. This process not only helps in substantiating product claims but also plays a crucial role in building consumer trust and compliance with regulatory standards.”
In much shorter terms, it’s making sure something works properly.
What happens inside the Cold Harbor room
Apple TV+The Cold Harbor room is the final Efficacy Test for Gemma’s severance chip. With her tempers balanced (or numbed), she doesn’t remember anything about who she is or why that room should cause her so much emotional pain.
Inside, there’s nothing but a crib – the same crib Mark bought before she had a miscarriage (hence why it was called “col d’Arbor” on the box). “Enter the room,” Dr Mauer orders as Jame watches through his screen.
“Who are you?” Dr Mauer asks. “I don’t know,” Gemma says, and she approaches the crib. “Take it apart,” Dr Mauer tells her, and Jame queasily watches as she slowly dismantles it.
“The barrier is holding. She feels nothing… it’s beautiful,” Dr Mauer says as Billie Holiday’s ‘I’ll Be Seeing You’ plays in the background (this song was also a mainstay on Mark and Gemma’s record player in their house).
Find out everything we know about Severance Season 3, and catch yourself up with our guides on the Eagan family tree and the Lexington Letter. If you’re looking for something else to watch, we’ve rounded up the best shows like Severance and all of the year’s releases in our 2025 TV calendar.
