(CNN) "Game of Thrones: The Last Watch" could easily be dismissed as HBO's way of maximizing its ample investment in the series, a glorified electronic press kit to extend the program's run by one more week. Yet after many viewers spent the final season bashing the show, the two-hour documentary served a dual purpose, offering a reminder of all the grueling work that went into making it.

Director Jeanie Finlay spent a year chronicling the production, spanning locations from Belfast to Croatia to Spain. While the stars and producers David Benioff and D.B. Weiss received a bit of screen time, the project went the extra mile to showcase those who don't walk red carpets, from background actors -- shown noshing on snacks during breaks, under hideous makeup -- to construction, the cheerful folks who fed this small army and even those responsible for all that fake snow.

Among the unlikely stars of the documentary were Andrew McClay, an extroverted background actor who choked up when his watch finally ended; and Vladimir Furdik, the stunt coordinator who garnered an unexpected taste of stardom as the villainous Night King, who muttered "Back to normal" when his stretch under that guise finished.

Finlay also spent considerable time presenting the weeks of night shoots -- prompting one crew member to mutter that he felt like a vampire -- amid inclement weather that pushed the production, and those working on it, to their limits.

Daniel Portman, Rory McCann, Sophie Turner, Kit Harington.

The stars did get their moments, from Kit Harington's tearful farewell on his final day of shooting to Emilia Clarke quietly musing in her makeup chair about what life will be like after the show, which both propelled her into the public consciousness and left a lot of people debating the wisdom of having named a daughter "Daenerys."

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