Gerda is a woman with white hair. Her age is unknown.
Although Gerda serves as Erik's right hand, and goes along with his plans, she is clearly more level-headed and rational than him. While Erik is mostly out for glory, Gerda is genuinely just trying to help people, and unlike him, she is willing to stop and listen to gain a better understanding of the situation. She also does most of the work.
She is generally nice and friendly to others, albeit a little bit dense about her surroundings at times, hence the reason why she speaks a slightly louder volume. Originally, she had a bit of dedication to Erik and appeared to admire him as well, until she witnessed Erik’s disregard for safety in favor of impressing everyone to achieve glory. She slowly grew disillusioned with her superior’s arrogance and became sick of his attitude. During their survival in the Woods, Gerda proved to be the only one out of the two actually capable of surviving, which shows she may have some experience with surviving in the wilderness.
Gerda is first seen in "Chapter 1: The Troll Circle", when she and Erik drop by at Hilda's house because Hilda won the first Annual Safety Patrol student essay contest with a story about her encounter with a troll. Her price is being allowed to go on patrol with Erik and Gerda for one day to check the city's Troll defenses. They start with an aerial patrol, during which Gerda pilots the Safety Patrol zeppelin. They fly through a group of arguing Weather Spirits, who zap the zeppelin. Gerda is barely able to avoid a crash. The three continue their patrol by car. When Hilda leads Gerda and Erik to a group of petrified Trolls that she saw outside Trollberg, Erik takes his time to have Gerda take some photos of him posing next to the trolls. They forget the time however, and the sun sets while they are still near the trolls. Gerda attempts to fight off a Two-Headed Troll with the car, but the troll wrecks the car. Gerda saves herself by using the cars inflatable shield, and urges Erik and Hilda to run while they still can. She is later revealed to have escaped the trolls by using the Vittra tunnels in the area.
In "Chapter 6: The Old Bells of Trolberg", Gerda is present during Erik Ahlberg's ceremony to officially introduce the new mechanical bell ringers that Ahlberg installed in all the bell towers. When Hilda and Frida sabotage the system by cutting a wire, Gerda quickly activates the backup system so the ceremony can continue. Hilda still manages to sabotage everything by putting the bells on maximum volume. This cause the bellringers to short out, and the bell from the central belltower to get dislodged. It lands on top of Erik, after which Gerda can be seen trying to free him.
In "Chapter 7: The Beast of Cauldron Island", Gerda assists Erik in his attack on Cauldron Island, where the Lindworm is supposedly sinking ships. They soon find out however that the real culprit is a Kraken. When the Kraken wrecks several ships and intercepts Erik's harpoon, Gerda is ordered by Erik to retreat.
In "Chapter 12: The Replacement", Gerda is alerted to the commotion at the Farmers Market caused by Alfur Aldric, the Bragga Family, and the Delegation for the Return of Wayward Elves. Like all the other humans present, she is unable to see the Elves and thus mistakes them for spirits. She hears voices coming from a Light House decoration, and takes it to Safety Patrol HQ to interrogate the Spirits, not realizing she caught a group of Elves instead. While Gerda admits that she doesn’t know anything about questioning Spirits, she gives it a try anyway. In a handbook about Spirits, she reads that Spirits will respond by submerging them in water, and decides to test this theory by filling the box she locked the Elves in with water. Alfur, who followed her to HQ, calls out to her, and claims to be a representative of the Spirit Safety Patrol. He convinces Gerda that these “rogue spirits” shall be dealt with if she releases them into his custody, and quickly puts together the proper paperwork for her to sign. Gerda believes him, signs the paperwork, and releases the Elves. While she and Alfur talk, Gerda drops a hint that she doesn’t like Ahlberg that much despite being his right hand.
In "Chapter 13: The Stone Forest", while Gerda and Erik are patrolling the area outside Trolberg with their zeppelin, they notice David and Frida, who are looking for Hilda. Frida accidentally startles a group of Woff, who collide with the zeppelin and cause it to crash. With no way to return to Trolberg before nightfall, the group spends the night in the woods. Gerda tries her best to keep the kids safe, especially after Frida accidentally transforms Ahlberg into a bug. During the night. Gerda comes to realize that the Trolls may not be as bad as she thought when one of them sits down at the campfire with them to enjoy some Jorts. The following morning, Alfur finds the group. While Gerda is still unable to see him, she recognizes his voice from their previous meeting, and is told by Frida what Alfur truly is. Together with David and Frida, she manages to restore build the emergency blimp from a kit they could salvage from the wreckage, and they use it to rescue Johanna from a landslide caused by the Two-Headed Troll. Once back in Trolberg, Gerda takes Frida and David to HQ so Frida can turn Ahlberg back to a human. She succeeds, after which Ahlberg immediately tries to rope the kids into giving a statement to the press about how he rescued them. By now, Gerda realizes how incompetent and egocentric Ahlberg truly is, so she quickly escorts the 2 kids out of the room, ignoring Ahlberg’s rant, and takes them home.
In "Hilda and the Mountain King", Gerda is seen several times accompanying Erik Ahlberg during his patrols outside the city and when he gives a press conference. She still tries in vain to point out the flaws in his plans, but gets ignored every time. When Ahlberg agrees to accompany Johanna to search for Hilda, he puts Gerda in charge of the cities defenses. When Trundle attacks the city, Gerda actually listens to Hilda's warning that fighting back would provoke Amma into destroying Trolberg, and refuses to attack Trundle. Ahlberg fires her for insubordination and kills Trundle himself. Fortunatley, Hilda is able to use Trundle's eye to make Ahlberg realize the danger, and he comes around. At the end of the movie, Ahlberg retires from the Safety Patrol and makes Gerda the new head. Her first order is to initiate The Night of the Trolls as an annual event that allows Trolls to be near Amma.
In the Hilda tie-in series, Gerda is a supporting character in "Hilda and the Time Worm", "Hilda and the Ghost Ship" and "Hilda and the White Woff". In the first two books, she is mostly a background character who appears in scenes along with Erik Ahlberg. She, along with Erik, comes to the Sparrow Scouts broth stand at the Trolberg Winter Festival to tell Hilda she won an essay contest, and that her price is going on patrol with them. She is also present during the ceremony where Erik plans to activate the new mechanical bellringers (which, like in the series, get sabotaged by Hilda). In "Hilda and the Ghost Ship", she participates in the attack on Cauldron Island. Near the end of the book, in a scene that was not in the animated series, she and Erik come to the windmill because their seismograph picked up the activity from Victoria Van Gale's machine. Erik refues to believe Hilda's explanation about what truly happened, and is convinced the seismic activity is from a large troll. Gerda realizes the kids told the truth when she sees a blueprint of the machine, but doesn't tell Erik this.
Gerda has a larger role in "Hilda and the White Woff", which adapts "Chapter 13: The Stone Forest". Her role is large similar to that episode. A major difference however is that Erik is fully aware of being transformed into a bug here, and after he is turned back to normal, he fires Gerda for her part in his ordeal (she put in in a thermos flask to keep him safe).
- Chapter 1: The Troll Circle
- Chapter 2: The Draugen
- Chapter 6: The Old Bells of Trolberg
- Chapter 7: The Beast of Cauldron Island
- Chapter 12: The Replacement
- Chapter 13: The Stone Forest