Starfish

Aubrey breaks into Grace's home because she is overwhelmed with grief and loneliness after her best friend's sudden death. She hopes that staying in Grace's apartment will help her feel close to her again, even though she has to squat there illegally. This personal tragedy becomes the emotional core that drives her to investigate Grace's mysterious work.

The Signal is a mysterious transmission that Grace discovered, which she believed could trigger or control the alien invasion. Through the cassette tapes she left behind, Grace explains that she found this Signal and hid clues about it. The walkie-talkie voice reveals that Grace discovered the Signal that ultimately caused the dimensional gates to open, bringing the alien creatures to Earth.

Grace's cassette tapes contain hidden messages explaining the Signal and directions to find more tapes she has scattered across town. They serve as a cryptic guide for Aubrey to follow, leading her to the grocery store, library, and cinema. The tapes are presented as humanity's possible salvation, meant to be played together at a radio station to close the dimensional gate.

When Aubrey plays all the tapes at the hilltop radio station, the walkie-talkie voice delivers a chilling twist: the tapes may have actually opened the dimensional gates further rather than closing them. This means Aubrey's desperate attempt to save the world by broadcasting the tapes has the opposite effect, potentially dooming humanity instead of saving it.

After learning that playing the tapes made things worse, Aubrey exits the radio station and confronts the dimensional gate directly. She steps into the antigravity field surrounding the gateway, causing her to rise and become suspended in midair. This surreal final moment leaves her floating toward the mysterious unknown as the world watches an unresolved, unsettling fate unfold.

An unknown person contacts Aubrey via walkie-talkie while she stays at Grace's home, claiming that Grace discovered the Signal that triggered the alien invasion. This mysterious caller hints at a hidden purpose behind the chaos and turns Aubrey's grief into a reluctant mission. The identity of this voice remains ambiguous throughout the film.

The invasion begins after Grace's death because she had discovered the Signal that triggered the dimensional gates to open. It appears that her discovery and the subsequent events are causally connected, Grace found something she wasn't supposed to, and this attracted or activated the alien threat. The timing suggests her work on the Signal directly led to the catastrophe.

Aubrey finds the hidden tapes by following cryptic visions and the clues embedded in each cassette. The tapes guide her to various locations in town, the grocery store, the library, and the cinema, where she searches for additional recordings while dodging aggressive aliens and mutated humans. Each location provides fragmentary clues that eventually lead her to gather all the tapes.

Reality begins fracturing due to the dimensional gate opening as a result of the Signal Grace discovered. The alien invasion brings creatures and changes that distort the normal world, creating the strange, dreamlike atmosphere where memories blur with reality. This fracture represents the barrier between dimensions breaking down.

Grace discovered the Signal that triggered the dimensional invasion, essentially accidentally opening the gateway that brought the aliens to Earth. She then tried to undo her mistake by hiding the cassette tapes with messages that might help close the gate. However, as the walkie-talkie voice reveals, her tapes may have only made things worse, leaving her role tragically ambiguous, was she the cause or a failed attempt at redemption?

The mutated humans are victims of the alien invasion and the dimensional breach caused by the Signal. As the gates opened, some humans were changed or corrupted by whatever forces are coming through. These mutated individuals prowl the shadows alongside the alien creatures, making Aubrey's search through familiar locations like the grocery store increasingly dangerous.

Aubrey's ascension into the antigravity field represents the ultimate consequence of her choices, she directly confronts the dimensional gate she may have unintentionally widened. The ambiguous ending suggests she either sacrifices herself to somehow fix what went wrong, or she is pulled into another dimension. Either way, the world remains in peril, leaving the story on a bleak, unresolved note about unintended consequences.