Dutch diver and underwater cinematographer Peter van Rodijnen captures bioluminescent algae, plankton blooms and devoted father fish in North Sea, Nature Untamed, a documentary that dismantles the perception of the North Sea as a drab wilderness.

The film opens with a provocation. The North Sea, with its cold grey waters, has a claim to being the world's drabbest stretch of ocean. Van Rodijnen spends the documentary's running time proving otherwise, and his voiceover, in the words of the Guardian's review, gives the film "an endearing eccentric charm."

The greyness goes first. Van Rodijnen films the North Sea's waves sparkling with what the review calls "the cosmic blue light of bioluminescent algae." He captures the water lit up in the disco colours of coral and plankton blooms. What reads from the surface as monotone reveals itself, through his lens, as a shifting spectrum of blue, coral and planktonic colour.

The documentary then turns to its cast of characters, and Van Rodijnen finds coo-worthy stories in the depths. The standout is the male shorthorn sculpin fish — "no looker, it must be said" — who spends the winter guarding his eggs, cleaning them and blowing fresh water over them. Van Rodijnen's camera is present for the hatching: baby fish emerge, "pop, pop, pop out of their pearly plump pink eggs."

The film does not shy away from the odder corners of marine biology. Among the quirky stories the review singles out is a barnacle with a superlong penis, a detail that sits comfortably within the documentary's affectionate, unsqueamish portrait of undersea life.

Basking whales and plankton blooms share the frame with these smaller domestic dramas, and together they build the film's central argument: that the North Sea is not a bleak, empty expanse but a populated and vivid one. The footage, described by the Guardian as stunning, does the persuasive work; the voiceover supplies the personality.

For audiences who know the North Sea only as a cold, grey neighbour, the documentary offers a correction backed by images rather than assertion. It stands as a case for looking beneath the surface of waters we assume we already understand — and for the value of a cinematographer patient enough to wait through a winter of fish eggs for the moment they hatch.