Orca

The Orca, sometimes stylized ORCA, is a fictional sonic device invented by Drs. Mark and Emma Russell which appeared in the 2019 Legendary Pictures Godzilla film Godzilla: King of the Monsters.

Godzilla: King of the Monsters
The Orca was originally built by Mark Russell and Emma Russell with the purpose of steering whales away from the shorelines. Five years after the events of 2014, Emma completed the Orca while stationed at Monarch Outpost 61 in Yunnan, China. She soon found an opportunity to test the device when Mothra hatched from an egg deep within the temple the site was built around. Despite initially sending her into a rage with an incorrect set of signals, Emma finally locked on to the proper "alpha frequency", resulting in Mothra becoming docile. Just after this triumph, however, Outpost 61 was raided by Alan Jonah and his band of mercenaries, who took Emma and her daughter Madison hostage, along with the Orca itself.

While Mark was recruited by Monarch to decipher the alpha frequency, Jonah took the Russells and the Orca to Outpost 32 in Antarctica, which was the containment site of Monster Zero, where Emma began analyzing his bioacoustics for the device. Later, after Monarch had arrived and Emma had released Ghidorah from the ice, she used the Orca to wake him up. When he began attacking the Osprey that Mark and the other Monarch personnel were hiding in, Madison snatched the Orca from her mother, altering the frequency to one that sent Ghidorah into a rage. He almost destroyed their Osprey, but Emma shut it down, and he resumed his attack on the Monarch Osprey.

Later, Emma called Monarch to explain her plans to awaken the Titans to curtail the damage humanity had wreaked upon the Earth. Afterwards, and despite protests from Madison, she used the Orca to awaken Rodan at Isla De Mara. Unfortunately for Emma, and the world at large, King Ghidorah took position as the Alpha Titan after Godzilla was apparently killed by the U.S. military's Oxygen Destroyer, and rallied the remaining Titans (excluding Mothra) to his reign.

With the world beleaguered by both Titan attack and the disasters they caused, Emma devised a plan to use Boston's Fenway Park stadium speakers to broadcast an Orca signal around the world, lulling the Titans into submission. Despite Alan Jonah's refusal to aid her, Madison took the initiative and stole the Orca, taking it to the stadium and enacting her mother's plan. It worked, and the Titans were calmed down and ceased their attacks.

Unfortunately, Ghidorah seemed to pick up on the transmissions and attacked the stadium, tearing down the speakers before targeting Madison herself, leading to the Orca being damaged. While Godzilla and Mothra, now in her imago form, arrived to battle Ghidorah and Rodan, Mark and a group of G-Team soldiers located the wrecked remains of the Orca in the stadium before being rescued by Emma, who had arrived in search of Madison.

When Ghidorah gained the advantage against Godzilla, Mark and Emma hastily restored the device to operational status, broadcasting a signal that enraged Ghidorah and distracting him from Godzilla. While a Monarch Osprey arrived to retrieve the group, Emma drove off in a humvee, leading Ghidorah away from the group to buy them time to escape. The Orca was damaged again for the last time when Ghidorah overturned the vehicle with a gravity beam blast, and its remains were presumably destroyed when Godzilla entered burning mode, incinerating Ghidorah and leveling what was left of Boston.

Alpha Frequency
The Orca's primary function was to emit a signal that all of the known Titans would respond to, allowing the user to pacify or manipulate them as they saw fit. When connected to a larger speaker system, such as those in Boston's Fenway Park, the signal could be broadcast on a global scale. The signals could be selected and adjusted via a touch-screen control panel in the center of the device. The baseline alpha frequency was composed of the vocalizations from both Godzilla and a human.