I worked out five possible perceptional scenarios that fit the presented film. (1) What you see is what you get – Ellie lived as the film presented her, and her trip to the cosmos (no pun intended) actually happened just as she perceived and reported it. (2) It was all a dream – Ellie is actually residing in a rubber room in a quiet little hospital, and the film represents a logical extension of her childhood dream to find life in the heavens. (3) Her life was real, but the trip was a dream. (4) Her life was real, but the trip was implanted inside her brain by the aliens, and the ship was in fact a portal which the aliens could use to travel to Earth. (5) The trip was real, but her life was a dream.
Which one is the most likely scenario, if we stipulate that this perceptional scenario actually happened? I believe the second scenario – the rubber room – is the most likely. Her childhood traumas, especially her parents dying, and her obsession with finding alien life all make this scenario more likely than the other, somewhat far-fetched scenarios. Tabling that scenario (since it’s no fun and kind of sad), among the other four I think the last one – the trip was real but her life was a dream – can be ruled out as illogical, though I think the idea itself is fun. If the trip was real, why bother presenting her life as a dream? Who daydreams about doing the laundry? If the third scenario were real – that the trip was a dream – than why was there eighteen hours of static on her recorder? This leaves two interesting scenarios: either the entire thing was real, or the aliens implanted the trip into Ellie’s brain after getting Earth to build them a portal.
If the entire thing was real, the movie doesn’t quite feel complete to me. The alien entity did not show itself, or give Ellie even the slightest bit of real information. I believe an eighteen year delay in producing the rest of the story – making a sequel – is problematic to this scenario. That leaves the rather fanciful idea that the aliens had us build them a bridge to our world. The aliens were advanced compared to us earthlings based on their technology, and there is no reason to believe they would willingly allow some human with potentially deadly diseases to have direct contact with them. Is this scenario too far-fetched? The way I see it, if the natives of the western hemisphere had been presented with the choice of either coming to Europe through a portal or inviting smallpox across the pond to play with their children, which would be the more logical choice? If the aliens in this film had the technology to bring Ellie to them, they by logical extension must have been capable of bringing themselves to her just as quickly. They would have been crazy to risk contact on their turf, so by logic I vote for the portal.