Union provided invisible effects to help tell the story of The Dig, now streaming on Netflix. Directed by Simon Stone and based on John Preston’s book of the same name, The Dig recounts Britain’s most famous archaeological dig and the discovery of the Anglo-Saxon burial ship at Sutton Hoo in 1939.
Ralph Fiennes stars as self-taught archaeologist Basil Brown, who is employed by Edith Pretty (Carey Mulligan) to investigate the burial mounds on her land.
While the art department did a good job constructing the mounds, they appeared very bright against the more muted, almost straw-colored, fields. Union rotoscoped and color graded nearly every mound in every shot to ensure they fit seamlessly into the environment throughout the film.
In one scene, where an excavation is taking place, one of the mounds collapses on Basil Brown. The Union team reconstructed the mounds in 3D, projecting the textures from the footage to capture all the detail. They then fractured the geometry into slabs of earth and simulated these as rigid bodies using SideFX Houdini. Millions of particles were then added to form the smaller debris and dirt as the earth crumbles and cascades over Brown. Some smaller grain simulations were also used as the ground collapse settles in the final shot.
The film’s story starts just before the declaration of war in 1939. A number of scenes feature military aircraft squadrons overhead. In one, an aircraft loses its engines and crashes near Sutton Hoo, skimming the nearby trees before hitting the river. The production managed to get a real plane to fly low enough to look convincing. Union’s VFX team then removed the propellers and added CG props that were almost static, moving just slowly due to wind. The studio then extended the tree line slightly higher and added an effects pass of leaves and branches being thrown from the tree as the plane clips it.
For the wider shots, the studio used its CG Spitfire plane model, which was based on the Hawker Hurricane that was active during the late 1930s and early 1940s. It features a distinctive black & white paint scheme on its underside, making it easily identifiable as a friendly aircraft from the ground. The studio then animated a squadron of these planes flying overhead in several scenes.
“One of the biggest challenges on the show was creating the surface bubbles where the plane had submerged,” explains VFX supervisor James Etherington-Sparks. “Mike Eley’s photography was so beautiful and natural, it made it very daunting to stick CG water inches from the camera. We began developing and testing solutions quite early on that gave us some very promising results. Ultimately, we were able to deliver photorealistic, dynamic water that fit the tone and style of the film perfectly.”
The team simulated and rendered bubbles in Houdini with turbulent forces to model the escaping air bubbling up to the surface. Below the surface, Union used particle systems and more fluid volumes to drive the behavior of the bubbles as they swirled around the fuselage of the plane. These were meshed together, rendered in Houdini and combined with elements in comp.
Other work included employing split screens when young Archie Barnes nearly gets knocked off his bike by a van as he cycles to try to persuade Basil to return.
There was also period clean up and blue-screen work, including a scene where Edith visits the doctor. The viewer sees her from outside, through a window, and then follow her as she comes downstairs and exits at ground level. Union was unable to gain access to the interior of the location, so that was shot against a blue screen and the camera move was tracked seamlessly.