A colossal alien spacecraft makes its landing in a North African village around 8000 BC. While most villagers flee in terror, one brave soul approaches the spacecraft, and he is mysteriously "taken" aboard. Fast forward to 1928, where Professor Langford uncovers an immense stone ring buried in the sands of Giza, Egypt. Upon examination, it reveals inscribed cover stones believed to hold the keys to operating these ancient rings.
In the present day, Langford’s daughter, Catherine (Viveca Lindfors), offers the opportunity for Daniel Jackson (James Spader), a linguistics professor facing professional setbacks, to translate hieroglyphs that could substantiate his controversial theory regarding the construction of the Pyramid of Khufu. Jackson, an archaeologist and linguist, contends that the Fourth Dynasty pharaohs did not actually build the Great Pyramid of Giza, a belief dismissed by the scientific community due to the absence of any inscriptions within the pyramids.
After accepting Catherine's offer, Jackson is introduced to a U.S. Air Force base nestled in Creek Mountain, Colorado. Here, researchers Dr. Barbara Shore (Rae Allen) and Dr. Gary Meyers (Richard Kind) are analyzing the recovered cover stones from Egypt, while Major General W. O. West (Leon Rippy) leads the project overseeing the ring device and its cover stones. Under West's command, Colonel Jack O'Neil (Kurt Russell), who has been grappling with the loss of his son and thoughts of suicide, is reactivated to manage the operation.
Upon translating the hieroglyphs inscribed on the cover stones, Jackson uncovers the phrase:
> “A million years into the sky is Ra, sealed and buried for all time, his Stargate.”
Colonel O'Neil is then briefed on the Stargate, a device constructed from a unique mineral not found on Earth. After deciphering the symbols, Jackson explains that they correspond to star constellations which will allow them to pinpoint a location in space, with one symbol indicating their point of origin on Earth. He discovers that the seventh symbol, a pyramid with a sun above it, is key to forming a stable connection back home.
With preparations underway, Jackson is included on the team selected to journey through the Stargate, and Catherine gifts him a medallion linked to their mission. Leading the expedition, O'Neil and his team step through the Stargate, finding themselves enveloped in the endless sands of a new world, a place dominated by a towering pyramid and three moons in the sky.
As they explore, Jackson warns that they cannot return home yet because the Stargate’s coordinates are incomplete; they need a cover stone similar to the one from Earth. O'Neil secretly engineers a nuclear bomb inside the pyramid, intending it as a failsafe. Venturing outward, O'Neil's team encounters a mining village inhabited by humans who mistake them for gods upon seeing Jackson's medallion. The leader, Kasuf (Erick Avari), welcomes O'Neil and his team.
Jackson soon realizes he can communicate with the locals, as they speak a dialect of Ancient Egyptian. He forges a bond with Sha’Uri (Mili Avital), the leader's daughter, while O'Neil befriends Skaara (Alexis Cruz). However, Jackson discovers hieroglyphics revealing that the Egyptian deity Ra was, in essence, an alien who used advanced technology to enslave humanity. History recounts how these humans eventually rebelled, sealing away the Stargate to prevent future oppression.
Just when the Earth team discovers the necessary cover stone to return home, disaster strikes. A massive spaceship descends on the pyramid, capturing or killing the entire team. O'Neil and Jackson find themselves in a throne room with Ra, who has ominous plans to send their nuclear bomb back to Earth, now repurposed to unleash catastrophic destruction. In a gripping showdown, Jackson is killed amidst the chaos, and O'Neil is imprisoned alongside the surviving team members.
Miraculously, Jackson revives thanks to an alien device while Ra’s threats loom nearby. Using newfound unity from the local tribe, O'Neil and the team orchestrate an escape amidst the uprising against Ra’s forces. With courage and cleverness, they leverage local support to return to the Stargate, but tragedy strikes as Sha’Uri is slain.
In a final act of resilience, Jackson resurrects her with Ra's technology, as O'Neil prepares to neutralize the bomb before Ra can use it. In a climactic moment, they transport the bomb back to Ra's ship in orbit, resulting in its destruction, taking Ra down with it.
Ultimately, the surviving team is able to return home through the Stargate, though Jackson makes the brave decision to remain behind, forging a new destiny on this extraordinary planet.
