Following their work as primary VFX vendor on the first season of Cobra, BlueBolt were brought back on board this time around to create a total of 260 VFX-heavy shots for the Sky Atlantic show.

COBRA S2 stars Victoria Hamilton and Robert Carlyle. It was directed by Al Mackay, Mo Ali and Sallie Aprahamian and produced by Joe Donaldson. The VFX supervisor at BlueBolt was Henry Badgett, with 2D supervisor Andreas Krein and CG supervisor Nic Birmingham.

Taking place during a national emergency, the story follows the activities of an elite team of crisis contingency planners as they try to prevent disaster. The key VFX sequence, which kicks off this series, starts as an underwater explosion which causes a CG tidal wave to sweep across a seaside town.

Filming for Cobra season 2 began in October 2020. The production was based out of Space studios in Manchester and made use of locations all over the Northwest, particularly featuring Fleetwood and Blackpool for the sequences containing the water FX. A small number of establishing shots were filmed in London, and there was a helicopter shoot over Sheerness in Kent where the main story event happens.

BlueBolt started working on assets in December 2020, shots started turning over in March, and the final episode was delivered in July 2021.

The VFX comprised a balance of 2D and 3D work. Producing a movie-scale tidal wave and flood sequence on a TV budget and timeframe was a challenge. “The water FX was at a new level of ambition for our studio, and also the clients hadn’t worked with this kind of VFX before. We had to take care to be clear about the process and manage expectations as we went through the sequence from start to finish,” said BlueBolt VFX supervisor Henry Badgett.

“For example, we had to persuade the client to green light the lookdev work on the water FX before their cut was locked as we needed the technical process to start as early as possible, and to some extent the early stages of this process were independent of any individual shot.”

The water FX were also particularly resource-hungry. “Managing the simulation and render times of the water passes was a specific production challenge, involving constant evaluation and trade-off between creative brief fulfillment, technical quality, render times and delivery-to-comp deadlines, working backwards from client review dates,” said Badgett.

Render times were long, so cloud rendering was used as much as possible to keep the farm from being overrun. “Houdini sims and renders are notoriously data heavy. As the project required a lot of water renders we had to be very economical in storage and only keep renders that made the final comp.”

Several sequences spread across two episodes were shot at an offshore wind turbine. This required extensive planning especially for shots in which characters transition on and off the platform; the environment was created as a combination of set build, drone footage, VFX turbine, and CG water extension.

Inevitably, the shoot experienced significant disruption due to the pandemic and in post the team were still adjusting to having almost everyone working from home with the exception of the Supervisor who was in attendance to review shots with the clients and QC the work in HDR nearer the end of the project.

As ever, these challenges were met and the team produced some outstanding VFX with key sequences in episodes 1 and 2, the water scenes, and episode 6, a car explosion.

Tanya Combrinck
Author: Tanya Combrinck

Tanya is a writer covering art, design, and visual effects. She has 15 years of experience as a magazine journalist and has written for publications including 3D World, 3D Artist, Computer Arts, net magazine, and Creative Bloq.