Thunder Road Pictures is gearing up to scale “Matterhorn,” developing the feature based on Karl Marlantes’ Vietnam War novel and setting it up with Matt Cook to write and direct.Marlantes, a highly decorated Vietnam veteran, spent more than 30 years writing the book. Iwanyk and Cook, an Iraq war veteran himself, forged a relationship with Marlantes when the book was first released in 2009 — leading led to a creative alliance to develop the project independently as a vehicle for Cook to direct before taking the project out. Thunder Road topper Basil Iwanyk will produce, while Kent Kubena will oversee for the shingle. The book is set in Vietnam in 1969 where Matterhorn is a fire-support base located between Laos and the DMZ. The key characters are a second lieutenant who’s a recent college graduate and his compatriots, most of whom are teenagers. Thunder Road is in post on “The Seventh Son” starring Jeff Bridges and Julianne Moore for Legendary Pictures. Cook has penned a pair of Black List scripts: “999,” which has John Hillcoat attached to direct; and “By Way of Helena.” Marlantes is repped by ICM Partners. Cook is repped by WME and Anonymous.