"After looking at this sci-fi short clip of the movie 4-5 times, you're enacting some kind of Wigner's friend in which each of you alternates between being the friend and Wigner. Wigner is performing a post-selected teleportation on the friend, which sends the friend back in a continuous stream of people, coming from the future, and going back. Possibly these people come from other branches of the universal wavefunction (because of Wigner's friend)."
"A quantum gravitational quantum computer is built, a unified theory of gravity is given. With this, a projective closed time-like curve (P-CTC) is implemented.
Along it, a Quantum Turing test [something like Wigner's friend] is performed. The Michele/Seth characters almost-kill each other, by not living up to their scientific mission. There is actually no death, their characters hallucinate and dream it. "From the inside" of the quantum computer (we already live in one) these are super intelligences modeling cooperation/defection of themselves. The Polaroids from the end of the movie indicate the knowledge of the other lives. That said, I don't think David Deutsch's thought experiment is physically possible. That is, once you build a quantum computer the possibility of asking any Artificial Intelligence living inside the quantum computer to give the qualia of it's memories from other worlds, I think you'd violate the physical universe's computational bounds. Steeplechase is indeed art about how that notion is probably wrong. It seems to violate computational bounds. BQP = EXP or something like NP"