In the Season 4 premiere, Artie Nielsen uses an artifact to turn back time 24 hours, and successfully finds a way to defuse the bomb that would destroy the Warehouse. Since he is successful in saving the Warehouse, Helena's death, her tragic hero's redemptive act of self-sacrifice, never happened. Artie later successfully advocates on Helena's behalf to keep her from being re-incarcerated. Helena becomes aware of this alternate timeline in " Second Chance ", after she deduces, in the previous episode (" Endless Wonder "), that Artie used a time travel artifact to save the Warehouse. Also in this episode, Mrs. Frederic tells her to take the astrolabe and hide it where no one can find it.