Myndin er byggð á samnefndri metsölubók eftir Arnald Indriðasonar. Óskar Þór Axelsson leikstýrir myndinni en fyrri myndir hans eru Svartur á leik (2012) og Ég man þig (2017). 

Napóleonsskjölin segir frá Kristínu (Vivian Ólafsdóttir), lögfræðingi sem dregst inn í hættulega atburðarás þegar yngri bróðir hennar, rekst á þýskt flugvélarflak úr seinni heimsstyrjöldinni á toppi Vatnajökuls.

English

In 1945, a German bomber crash-lands in Iceland during a blizzard. Puzzlingly, there are both German and American officers on board. Flash forward to the present. The U.S. Army is clandestinely trying to remove the wreck of an airplane from an Icelandic glacier. A young Icelander, Elías, inadvertently stumbles upon the excavation and then promptly disappears. But before he vanishes, he manages to contact his sister, Kristín. She embarks on a thrilling and perilous adventure, determined to discover the truth of her brother's fate