Season 3: We meet Eva when she approaches Jonas in her world, and tells him of how their two worlds are connected in that they both are stuck in time loops, destined to live the same lives over and over because of him . . . and herself, aka Martha. If Adam is the keeper of the time loops in his world, Eva is the keeper of the loops in this world, doing everything she does in order to ensure that her and Jonas's son is born. Throughout the season she's seen following through with actions that complete the cycle, sending her son out to do most of her bidding, in addition to Bartosz, Noah, Claudia, and Egon. In terms of Eva in the origin world, Martha doesn't exist there, thus she can never give life to her alter-ego.