Terminator timelines theory
I like the Terminator franchise. I wholeheartedly agree with the more or
less general consensus that Terminator 2 is one of the best
sci-fi movies ever made.
Of course the movies leave quite many questions about their internal
logic (especially related to time-travel and how it affects the timeline)
unanswered, and they could be considered outright plotholes. On the other hand,
it's a fun exercise to come up with plausible explanations for these
I present here a graph of my theory of the four Terminator movies. The
contents of the graph are explained in more detail in the
questions and answers
I will consider only the four movies here. I won't consider the TV
series nor the different video games and other works as part of the "movie
canon" (although they could work as separate timelines, except that some
details in them contradict my theory).
I make the following assumptions in my theory. They are explained in more
detail in the questions and
- Every time anything is sent to the past, the timeline splits. Whatever
was sent to the past ends up in an alternate timeline which does not affect
- Ontological inertia: Even if an attempt is made to change a timeline,
the events of the timeline will nevertheless gravitate towards the same
events of the original timeline (or events which have an equivalent
outcome will become more likely). In other words, significant events
tend to be preserved, even if it means that they happen with a delay.
- For some physical and/or technical reason there are only a few narrow
time windows to which anything can be sent back in time. These time windows
are located at 1984, 1995 and 2004.
- Because of some physical reasons or technical limitations (eg. available
energy) the earliest possible time window reachable from around 2026 is
the 1984 time window. (As Skynet's own time advances, at some point it
becomes impossible to reach the 1984 time window anymore, and the next
available one is the 1995 time window, and so on.) The time window previous
to 1984 is so far in the past that it's not reachable by Skynet.
- Likewise because of technical reasons (time travel energy requirements
and available resources) only one terminator can be sent at a time.
The timeline graph
Click on the image for a larger version. Also a
PDF version is available.
- The Skynet in the original timeline might also have sent a T-1000 to the
1995 time window, and possibly a T-X to the 2004 time window (when it had
gathered the resources and developed the necessary technology to do that).
The reason for sending the T-1000 to 1995 is the same as in the other
timelines (to kill John Connor himself before Judgment Day). In this
timeline 2004 is well after Judgment Day, but sending T-X anyways to
kill John Connor makes sense because Connor is still not the resistance
leader and not prepared for such a powerful Terminator.
- Likewise the Skynet in the 1984-timeline may have sent a T-X to 2004
for the exact same reason.
- Because of ontological intertia, all the Skynets in all the timelines
send the T-800 to 1984, as well as the other Terminators sent "before"
the spawning of the corresponding timeline. In the 1995 and 2004 timelines
this probably happens later than in the original and 1984 timelines (because
Skynet was created later). However, it doesn't happen so much later that it
would miss the 1984 time window. These time travels create alternate
timelines, not seen in any of the movies.
- This happens eventually also in the 2004-timeline, but this is not
marked in the graph because the current timeline "head" is at the fourth
movie tag (so sending the Terminators back has still "not happened").
- The numbered "movie" tags are, naturally, Terminator,
Terminator 2: Judgment Day, Terminator 3: Rise of the
Machines and Terminator Salvation.