After watching the film all the way through, Pippa's revenge-filled twist ending makes a lot more sense. Looking back, the close-ups of eyeballs behind the opening credits and the soft-boiled eggs being sliced during transition scenes tell us that what we're seeing is flawed. This same symbolism comes across when Thomas breaks one of the binocular lenses but Pippa continues to use them, and again when the lead optometrist at Pippa's clinic gifts her with a bird feeder.
The box is covered in a bird-themed wrapping paper — a possible callback to Alfred Hitchcock's The Birds — and the fact that the bird feeder is shaped like a lantern indicates that it's meant to illuminate something in Pippa's life. "When you see birds drinking from this outside your window, let it be a little reminder of how imperfect our own species' vision is," the optometrist tells her, further foreshadowing the lies Julia and Sebastian reveal to Pippa later on.
After Thomas's death — foretold by his "Curious" brand chlorophyll water — Pippa clears her stuff out of the apartment to get a fresh start. When she takes down the bird feeder, which Thomas filled with poisoned chlorophyll water, she looks down to find eight dead birds on the grates beneath the window. In this way, the lantern alerted Pippa to the fact that Thomas was actually poisoned and further tied into the film's overall message that "things aren't always as they seem."
