well not realy but here my theory of the puzzle after seing the first 2 episodes plot :

I think its some guys from the futur capture the prisonners in 1963 bring them back in futur trained them and probably brain washed them for missions that they will do in the past to alter the course of time by resending them in time.

these prisonners mission is mix with their personnal revenge on people that did armed them while been prisionners in 1963 or just their psyco comportments.

First prisonner killed (personnal goal) few guys when he respawned in the present but the main mission for the futur guys that they trained him was to get a Key.

Second guy the sniper was a serial killer and did the same when he respawned but the mission was to kill the assitant Lucy Banerjee

and the new prison underground in the Forest is there like a bunker to not being detect by the guys from the Futur.

that all the pieces of the puzzle i think of...By the way I hate the 2 main character choices (the blond girl and the fat guy) but for Sam Neill from Jurasic Park He's doing a great job