The 2nd Jack and Vicka

Question

Why did the 2nd Jack seem so hostile? The 1st Jack did not hesitate for a moment to put his life on the line once he saw people.

I'd have expected 2nd Jack to have been bemused, surprised and perhaps little shocked at a look alike, but when that look alike advised him to shut down the drone I'd expect he'd have done so promptly while they sorted out the apparent mystery.

And why wasn't the 2nd Vicka observing the 2nd Jack? The 1st Vicka seemed to watch the 1st Jack obsessively. The only time the 1st Vicka lost sight of the 1st Jack was when he was deliberately trying to avoid her, or going down into dangerous places to find a drone. The 2nd Jack was clearly visible in broad daylight.

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In lieu of a sourced answer, I will give the tick to the most plausible answer presented.

Answer 1

These are my thoughts, the up or down votes can determine how plausible it is.

All evidence suggests that if the first Jack was not unique amongst his kind, he was certainly rare. In fact, let's go with 'rare', since on his arrival at the Tet, it correctly predicted he was being deceitful, and challenged him on it. It probably had other 'malfunctioning/ineffective' Jacks (and possibly Vickas) on which to base its assessment. Oh, the disadvantages of being a clone..

In any case, he could not have been common, or the Tet would have abandoned that approach long ago.

So the 2nd Jack (in contrast) was part of an 'effective team', having no idea of the past, and fully believing everything Sally told him via his Vicka. Seeing a version of himself, he might have immediately suspected the Scavs had found a way to clone him, or at least take on a camouflage intended to lower his defenses.

But the first Jack had his faith in the information he was given eroded over time, he had become quite distrustful, and was questioning everything, as well as deliberately and wantonly breaking protocol etc.

It was this precursor breakdown that made him more willing to save the astronauts, or perhaps even investigate the pod rather than simply fire on it from a safe distance. Or, as Sally ordered, not to visit it at all.

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Vicka on the other hand, knew of Jack's doubts. At one point he makes a suggestion and she sort of groans with a 'not that again' type of reaction.

Although she was assuring Sally they were an 'effective team', she was living in a kind of denial, trying to convince herself of the same thing she was telling Sally. Besides, it had already got to a point where they had only 2 weeks left on their 'rotation' on Earth and she was just trying to get through those two weeks, intending to have a 'long serious, talk about our relationship' (I could feel all the guys shudder as I wrote that) as soon as they made it to the Tet.

So Vicka was paranoid because of Jack and watched him more closely and obsessively than was usual for 'a regular Vicka' to watch 'a regular Jack'.

Answer 2

Vicka #1 uses the drones to observe Jack #1. When Jack #2 fights Jack #1, there aren't any of her drones in the immediate vicinity which means that Vicka #2 is blind.

We see Jack #1 working without the drones on several occasions, calling them in for support only when he feels threatened. There's no reason to assume that Jack #2 doesn't also do the same.

As to why Jack #2 is "so hostile" you have to remember that he's suddenly been confronted with someone who looks identical to himself. He points his gun at the apparition (as you would), at which point Jack #1 attacks him. The hostility is all on the part of our hero, Jack #1