Tankograd is a riveting documentary film that explores the unique world of the city of Chelyabinsk, or Chelyabinsk-65, lovingly nicknamed as Tankograd by its enduring residents. The film, directed and co-written by Boris Bertram and co-written by Jesper Jack, takes viewers on a profound exploration of this erstwhile secret city that is as much a testament to man's indomitable spirit as it is a stark reflection of the catastrophic repercussions of strife and arms race.

Tankograd, literally "Tank City," comes alive in the film as a spatially confined entity shrouded in the grim lore of the past and dire consequences for the future. The 75-minute cinematic presentation, mostly in Russian, with English subtitles, was created in 2009. The documentary does not have a traditional cast, as is the norm with this genre, and instead shines the spotlight on real people with true stories that are as gripping as the eerily arresting landscape that forms the backdrop.

Bertram's camera vividly captures the contrasts and paradoxes of the Siberian industrial city, which was Russia's major arms producer during the Cold War era. It was responsible for manufacturing the bulk of tanks, missiles, and armored vehicles for the Soviet forces. The city was so enshrouded in secrecy during the Soviet regime that it did not even feature on maps and was referred to only by its postal code.

The director exploring the city's existence, unveiling the layers to its secretive past while also raising questions about its future amid a rapidly changing global scenario. The heart-wrenching stories of former factory workers, army personnel, and their families create a poignant narrative tapestry that mirrors the city's stamina and resilience against enormous odds.

Notably, the city also houses the Chelyabinsk Contemporary Dance Theatre – a dance ensemble of sheer passion and talent that infuses creativity against the gloomy, gritty industrial landscape. Tankograd brings this ensemble into focus, using their performances as a visual metaphor that resonates with the reality these artists inhabit.

The film beautifully juxtaposes these sequences of powerful dance performances with raw footages from old Soviet propaganda films and the contemporary ruins of the city. The strength, vitality, and tenderness of the body become an expression of life amid visible decay and desolation.

Furthermore, the director takes a thoroughly detailed look at the environmental issues the city grapples with. Tankograd also bears the dubious distinction of being one of the world's most contaminated cities, thanks to its unnerving legacy as a munition-producing center. The city faces extreme pollution levels, with its air, soil, and waters continually poisoned by radiation and heavy metals. The film is unflinching in its provoking portrayal of this environmental disaster, thereby highlighting the grave cost humanity pays for militaristic ambitions.

Bertram courageously uses various narrative tools, from deeply personal storytelling to thought-provoking imagery, to capture the dichotomy of this city's existence – its cheerless past and uncertain future. The documentary creates a compelling human portrait that doesn’t shy away from representing truth but also inspires a spark of hope through the indomitable spirit of its residents, who persist and dream despite everything.

Tankograd is an unraveling of complex themes of environmental degradation, human resilience, and the burdens of war, woven into a poignant tale of a city and its people. This film explores the hidden histories and unspoken truths that encapsulate our global narrative and provide an intimate insight into the resilience of humanity.

In summary, Tankograd is a must-watch for those who thrive on well-researched, deeply pensive, and visually powerful cinematic experiences. The documentary does not merely present an account of a place or its people but instead poses a compelling query – what are the true costs of progress and at what price comes survival?

Infused with elements of tragedy, resilience, and indomitable hope, Tankograd is a film that manages to seep into the heart of the viewer and instill a sense of retrospection. It forecasts, through its exploration of Chelyabinsk, a potential future if mankind continues to tread on the path of unchecked industrialization and militarization. Essentially, Tankograd is an act of leveraging cinema as a tool for shedding light on the darker corners of our history, thereby hoping to change the trajectory of our future.