The mechanical claw has considerably less finesse than the camera accompanying it. Through the underwater footage in Eleanor Mortimer’s How Deep Is Your Love, an unfamiliar organism becomes something we can watch moving through its own habitat.
The grabber makes it available for closer study. Brought to the surface, it cannot survive the change in pressure. These two instruments serve the same expedition, but they give the spectator different privileges: one permits observation at a distance; the other delivers knowledge through a fatal encounter. The beauty of the recorded animal makes that distinction difficult to dismiss.
A researcher’s comparison of himself to Nicole Kidman’s taxidermist in Paddington gives the discomfort an unexpectedly comic form. It is a joke made by someone who understands the accusation it contains. Mortimer allows the scientists’ enthusiasm and regret to coexist, refusing to make either feeling cancel the other.
Their work requires specimens; their affection for those specimens remains sincere. The camera’s intimacy with the researchers matters here. We see their concern, and that concern encourages us to accept the necessity of what they do. The film also supplies enough evidence to make acceptance uneasy.
Mortimer accompanies marine researchers into the Clarion-Clipperton Zone of the eastern Pacific, where plans for mineral extraction lend urgency to the study of a scarcely understood ecosystem. Her underwater images give that urgency a physical object.
Translucent bodies, improbable shapes, and brilliant colors occupy the screen with a clarity that exceeds our ability to explain them. We can inspect appearances without understanding relationships. That gap between visual access and ecological knowledge is one of the documentary’s strongest effects: the footage offers an extraordinary degree of detail while repeatedly reminding us how little detail alone can establish.
The cuts from these organisms to the scientists’ delighted faces quietly organize our response. Mortimer gives us experienced observers who still look surprised, making expertise compatible with astonishment. Their excitement lends the creatures value before taxonomy can give them settled identities.
Temporary names such as “Headless Chicken Monster” and “Psychedelic Elvis Worm” perform a related task. Faced with unfamiliar anatomy, the researchers reach for familiar absurdity. Scientific classification will take time; Elvis is available immediately. The names make the animals memorable, though the film leaves visible the distance between remembering a creature and understanding its place in an ecosystem.
Mortimer extends this playful intimacy when she asks a scientist to imagine meeting an arthropod, prompting a fantasy about taking it on a date. The exchange exposes the impossibility underneath the affection. A human encounter with this animal requires mediation, and physical contact carries consequences the fantasy can conveniently forget.
Her conversational voiceover suits that uncertain position. She speaks as someone trying to find a relationship with what she sees, rather than claiming authority over it. The hushed delivery sometimes makes the words harder to catch, however. Intimacy loses some usefulness when the information carrying it becomes indistinct.
The use of Portishead’s “Glory Box” around the research and collection material gives this attraction an uneasy emotional coloring. The song’s sensual pull accompanies a process in which fascination and possession sit uncomfortably close.
Mortimer does not need to accuse the scientists of greed for that association to register. The specimen’s fate has already complicated the pleasure of looking. Nor does the documentary establish a moral equivalence between limited scientific sampling and industrial extraction. Purpose and scale matter. Its sharper question concerns the uses to which knowledge can be put once it leaves the hands of the people gathering it.
That question becomes explicit when an activist vessel approaches the expedition and challenges the researchers’ role. Their investigation can be understood as a means of protecting the seabed or as preparation for exploiting it. Studying the mineral nodules makes that ambiguity concrete.
The scientists cannot settle it simply by demonstrating good intentions, because the findings may serve interests they do not control. Mortimer’s sympathetic proximity to the team makes this interruption valuable. Affection has brought us aboard; the encounter forces us to consider how the same work looks from another ship.
The documentary’s suspense develops through incompatible clocks. Nodules form over immense geological timescales. Identifying and describing a species can consume years. Commercial interest proceeds while researchers are still assembling the knowledge needed to assess damage.
Uncertainty becomes a vulnerability: the absence of a complete account leaves the scientists trying to establish what could be lost before anyone has finished counting it. The expedition’s patient curiosity gains tension from this pressure without requiring the crew to behave like adventure-film protagonists. Their ordinary work already takes place under a deadline they have little power to set.
At the International Seabed Authority’s headquarters in Kingston, Jamaica, Mortimer encounters a different limit on observation. Her camera can reach remote marine life through sophisticated equipment, but it cannot enter certain human meetings. Offices and corridors become the accessible surfaces of an inaccessible process.
This restriction gives the institutional passages their frustration, though it also limits their analytical reach. Waiting outside conveys delay and exclusion; it cannot reveal every argument, bargain, or responsibility inside. The film is much more intimate with the researchers than with the machinery determining how their research will be used.
Mortimer’s final superimpositions bring the creatures into those offices and corridors. The composite images alter the relationship between the building and the life discussed within it: organisms previously accessible through expedition footage now share the frame with institutional space.
The gesture is whimsical, but its placement gives it force. It makes the habitat difficult to keep mentally separate from the administration of its future. At the same time, the fantasy retains the documentary’s problem of access. Mortimer can place an animal in the corridor through an edit; she still cannot follow it into the closed meeting.
How Deep Is Your Love arrives in UK cinemas on October 2, 2026. The documentary follows an expedition vessel traveling deep into the remote Clarion-Clipperton Zone, exploring the mysterious and unfamiliar ecosystem hidden beneath the dark open ocean.
Where to Watch How Deep Is Your Love (2026) Online
Full Credits
Title: How Deep Is Your Love
Distributor: Independent Theatrical Release, festival distribution
Release date: October 2, 2026 (United Kingdom)
Running time: 1 hour 40 minutes (100 minutes)
Director: Eleanor Mortimer
Writers: Eleanor Mortimer
Producers and Executive Producers: Jacob Thomas, Muriel Rabone
Cast: Eleanor Mortimer
Director of Photography (Cinematographer): Eleanor Mortimer
Editors: Nicole Hálová, Maya Daisy Hawke
Composer: Fraya Thomsen
The Review
How Deep Is Your Love
Mortimer makes the pleasure of looking inseparable from the cost of knowing. Her extraordinary underwater footage and affectionate portrait of the researchers give scientific discovery a troubled conscience, while the final superimpositions bring threatened life into the institutions deciding its future. The political investigation remains limited by closed doors, and the hushed narration occasionally sacrifices clarity. Yet the film’s curiosity survives its uncomfortable questions, allowing wonder and responsibility to occupy the same frame.
PROS
- Underwater imagery makes ecological stakes tangible.
- Scientists’ enthusiasm and regret receive thoughtful treatment.
- Humor makes unfamiliar creatures memorable.
- Final superimpositions connect marine life with institutional power.
CONS
- Restricted access limits scrutiny of political negotiations.
- Hushed narration occasionally obscures information.
