A lowly utility worker is called to the future by a mysterious radio signal, he must leave his dying wife to embark on a journey that will force him to face his deepest fears in an attempt to change the fabric of reality and save humankind from its greatest environmental crisis yet.
The film is set on Earth in the year 2067, after it has been devastated by a complete collapse of the atmosphere. With all plant life on Earth extinct, civilization has collapsed around the globe; only one city in Australia has been barely able to hold out against these catastrophic changes, owing to artificial oxygen produced by the Chronicorp corporation. However, this oxygen is synthetic and gradually causes a deadly affliction known as The Sickness.
One day, Ethan Whyte, a tunnel worker for the city’s power plant, is faced with the harsh fact that his wife Xanthe is afflicted with the Sickness. The next day, he is called before Regina Jackson, a Chronicorp research CTO, who explains that the Sickness will eventually wipe out humanity. During a test of the Chronicom, a prototype time machine Ethan’s late father, quantum physicist Richard Whyte, had worked on before his death twenty years prior, the scientists received a radio signal from 407 years in the future with a message to specifically send Ethan to them to prevent the extinction of mankind. Despite the chance that Ethan might never be able to return, and his resentment against his father for apparently prioritizing his work over his own son, Xanthe and his guardian and work colleague Jude manage to change his mind.
After surviving the traumatic time displacement, Ethan finds himself in a lush but lifeless rainforest, with only a device permanently fitted to his wrist by his father during his childhood and a hand computer named Archie as his only surviving pieces of equipment. Following Archie’s instructions, he finds the entrance to a bunker-like structure, and before it, a skeleton wearing his jumpsuit with a bullet hole in its skull, as well as a decaying Archie and the familiar wrist device. Shocked by the discovery of his apparently inexorable death in the near future, and sick from eating poisonous berries, he finds himself rescued by Jude, who followed him through time after his life readings, transmitted through the Chronocrom, were failing. After sharing their findings, they follow Archie’s directions to another, still-functional bunker, which is revealed to be a Chronicom lab. It is there that Ethan’s wrist device is revealed to be a DNA analyzer specifically made to grant him access to the Chronicom, which sets itself for automatic reactivation in four hours. From a holographic recording left by Richard Whyte, they learn that the Chronicom project originally entailed the reactivation of an atmospheric monitoring station which would ascertain the Earth atmosphere’s breathability in the future and then transmit the data back to the past. When first activating the machine, Nathan was surprised to receive a message to send his own son to the future, so despite his misgivings, he prepared Ethan’s wrist analyzer. However, an immediate follow-up mission was rendered impossible because safely sending living matter through time requires an operational link from both sides.
The activation of the Chronicom triggers a malfunction in its nuclear power core, threatening to unleash a nuclear explosion before the countdown is completed. Ethan and Jude make their way to the power core, which is located beneath the overgrown ruins of their home city. Finding the ruins littered with skeletons, including Xanthe’s, they are forced to conclude that a cure against the Sickness was never found and a nuclear event took place. When Jude attempts some comforting words, Ethan recognizes his voice from a recording he found on the decaying Archie computer, taken moments before his future self was killed. Exposed, Jude directs Ethan at gunpoint to the reactor’s control room. Unable to activate the emergency override, Ethan willingly allows himself to be locked inside the depressurizing chamber to initiate a manual reboot. He succeed in rerouting the power, preventing the meltdown, and reopening the control room.
With 37 minutes to spare, they return to the Chronicom lab, where Ethan finds another exit that opens to the entryway with his skeleton. Upon its sight, Ethan suffers a nervous breakdown and implores Jude to kill him, which Jude refuses. Jude then confesses that there was no actual hope of ever-changing the future; refusing to believe that, Ethan locks Jude in and plays back the remainder of his father’s last message. From it, he learns that his mission was a sham from the beginning: Jackson intended to flee from her dying timeline into the future with just a few chosen to start anew, while Richard maintained the hope that the return message must have been sent by somebody, indicating that there is yet hope for all mankind. In order to prevent its abuse, Richard keyed the time machine to Ethan’s DNA, but when Richard’s colleague announced that the machine could be rigged to send a person into the future one-way, Jackson killed Richard. Jude, who had accompanied Jackson, was appointed as Ethan’s guardian to ensure the full use of the Chronicom when the time was right.
Refusing to allow this, Ethan tries to shut the Chronicom down, but Jude breaks out and moves to stop him. When Ethan refuses to fight him, Jude, guilt-ridden, commits suicide. Just before Jackson can put her plans in motion, Ethan sends the “Send Ethan Whyte” message, a copy of Richard’s recorded murder, a large collection of live jungle plants, and a personal farewell gift to Xanthe back to the past and then permanently shuts down the Chronicom. This creates a significant change in the time continuum: In the past, Jackson is arrested and the plants are used to revitalize the planet; and in the future, Ethan returns to his home city to find a thriving, highly advanced and populated civilization.
“Imagine for a moment we are all connected by the fabric of the universe. An invisible field that bonds us together, everything in the universe. You, me, the stars, we are all connected through time. So you see Evie, even when I’m not with you, we are always together.”