“ Black Bag ,” an elegant, quick-witted new thriller that finds Cate Blanchett and Michael Fassbender playing married spies, isn’t the pair’s first time together on screen. That honor goes to 2017’s “Song to Song,” one of Terrence Malick’s most intangible and head-scratching offerings — though the two stars can barely recall that experience.

Woody Harrelson, Simu Liu, and Peaky Blinders breakout Finn Cole are saturation divers Duncan, Dave, and Chris, tasked with repairing trans-ocean oil pipelines on the sea floor. Along with several other three-man crews, they work off of the dive support vessel Tharos, which, on this mission, has to sail into a storm.