Astrid is one of the series' protagonists, and was introduced as a Junior FBI Agent, doing research work for Olivia Dunham on her cases and became involved in a multi-agency task force of the U.S. Department of Homeland Security called the Fringe Division, dealing with supernatural events that are linked to experimental occurrences.

In the fourth season, due to the alternate timeline, Astrid is now a field agent, and also takes on a larger role, particularly the episode "Making Angels."

Following a plot line in the second season, viewers are introduced to Astrid's doppelgänger from the parallel universe who is an autistic computer and statistics specialist within the Fringe division.

In the fourth season's alternate timeline, Astrid acts as a field agent, based on the effects of Peter ceasing to exist as an adult from the events of "The Day We Died" in order to ensure both universes work together.

Astrid attempts to ease her grief by telling her that her own father is distant and also has a hard time expressing his feelings, but that she knows he loves her in his own way.

Her counterpart leaves seemingly reassured, and Astrid returns home to a loving and doting father, revealing that she lied to her double to make her feel better.

In "Brave New World", Astrid demonstrates adept combat skills by defending Walter and taking out several of William Bell's henchmen as they try to locate him, before she is shot in the stomach.

In the fifth season, Astrid, along with Olivia, Peter and Walter are freed from amber after 21 years due to the Observer takeover and are now part of a resistance to remove them from the current timeline.

He wondered how some of the events mentioned fit into the larger story arc, but found that the episode "offers its own refutation for those who get frustrated trying to figure out what's what.