Donna was Ryn's sister. She was separated from her sister when she captured in the sea one night. She took the name of Donna when she escaped from the government facility.
A mystifying and deceptively powerful mermaid.
Donna and Ryn's mother died when they were young so she assumed the role of raising Ryn.
At some point, she had befriended a merman, mated with him, and bore him a daughter who has taken the nickname Cami.
Donna had smooth dark skin in her human form. She also had thick, poofed and curly black hair accompanied with beautiful blue eyes. Like her sister, Donna was an attractive woman in her humanoid form (this is evident when most of the U.S. military and Aldon Decker were drawn to her).
Donna, in her mermaid form, had the upper-body of a human and the lower-half of a spiky, long fishtail. Along with that, she had small sharpened teeth, large glassy eyes and exposed ribs. She also still maintained her thick and curly black hair.
Donna was naturally aggressive and violent when it comes to prey, either fish or human. Her killer instincts and hatred towards humans have only grown due to being experimented on by the military's scientists.
However, after seeing how Ryn acclimated with human culture, Donna began to show a softer side towards Ryn and her human friends, a more human side. Donna became less aggressive and more caring before her death.
Throughout the Series
Donna and her sister Ryn were swimming in the ocean, searching for food, when Donna was captured by a group of fishermen, Xander McClure, Sean McClure and Chris Mueller and Calvin. However, her entrapment was unintentional and they had no idea that she was a mermaid upon her capture. When Chris came at her with an axe, she attacked, severely wounding Chris before running for cover. She remained hidden until a Navy SEAL team arrived and hauled her away in a steel chamber after shooting her with tranquilizing darts.
Donna was then taken to a military base and placed in a rather large fish tank. There, she was used as a lab experiment and underwent through needles drawing up her blood and grapples to keep her from thrashing around. Because of that constant torture, her hatred towards humans greatly increased. When she was alone with Aldon Decker, she sang her Siren Song to him. Then one night, as she was about to have her blood and DNA be extracted again, she finally escaped, whilst she killed many of the scientists and technicians and fled with Chris. Then she and Chris took a car and rode out to Libbey Beach where she reunites with Ryn.
A month after that, she and Ryn returned to land to try to find help as the over-fishing is depriving them of food. However, she did not trust humans at all, thanks to the time spent in the military facility. After feeling betrayed by Ryn, as she sided with Ben, Maddie, and Helen, she set out on her own, trying to find food. She then attacked a man working in the fisheries. The next day, she took refuge underneath a pier, where Helen found her and gave her fish. Helen took her to her home and revealed to Donna that she is one of them. This sparked a friendship between the two.
Donna has Helen made Maddie bring Ryn to her so that they can discuss matters involving their relations with humans. When they were alone, Ryn and Donna argued about whether to trust humans. Donna believed that humans must pay for what they did to her, but Ryn was against such unnecessary bloodshed. During the night of Elaine Pownall's charity event, Donna and Ryn teamed up to ambush Decker and used their Siren Songs to lure him and, unintentionally, Ben and Maddie. The two sisters attacked Decker until Ben put a stop to it. They both leave but later part ways when Donna believed Ryn chose humans over her. She returns to the water and swims back to her colony, while Xander tried to catch up to her.
One night, when Ben, Calvin, Chris, Xander, and Sean onboard the North Star explored an abandoned ship where a struggle occurred, Donna and a merman warrior Levi attacked them. When Chris and Calvin scanned for any other mermaids whereabouts, Donna sang her song to Chris and almost succeeded until Calvin shot a flare, distracting her and forcing her to flee. She then tried to kill Chris and Ben with a spear but got knocked overboard when Ben pushed her off with a crane holding a net. She then retreated with Levi after the latter killed Sean by stabbing him with a spear.
During Sean's funeral, Donna, still wanting to get Ryn back to the water, brought Levi and the alpha mermaid of her colony, Katrina, to find and bring her back. The three then stumbled around naked until they encountered three humans and steal their clothes. Donna took Levi and Katrina to Helen's store to ask Helen about Ryn's whereabouts, but when Helen did not know where she was, Donna left with Levi and Katrina. Eventually, Donna and Ryn reunited but later discovered that Levi and Katrina actually came with her to kill Ryn for spending too much time on land and with humans. Donna then sided with Ryn, Ben, and Xander as her allies fought against Katrina and Levi. However, near the end of the battle, Xander, who tried to avenge his father's death by killing Levi, unintentionally shot Donna through the stomach, leaving her in a critical condition.
Donna struggled for her life as she further succumbed to the bullet wound. Decker tried to save her with her blood but unfortunately they were extracted when she was mermaid form, Donna then died in Ryn's arms. This caused great grief for Ryn and the others, especially Decker, who believed that she sang to him because she loved him. The song Donna sang to Decker caused him to commit suicide by drowning. Donna's body was then taken to a secret hallowed cemetery where Helen's ancestors and other merfolk who died in Bristol Cove in human form were buried. There, Ryn, Ben, Maddie, and Helen paid their final respects to her after they buried her.
Ryn visits her gravestone with an apologetic Xander in the premier. Weeks later, Nicole notices the resemble in Cami after witnessing the video clip of Donna when she was being experimented on in "The Lure".
It is at her grave, that Ryn and Katrina come to a truce after Ryn makes her realizes they can't get home by themselves; that the only way for them to return home is with the help of the humans.
Many weeks later, Nicole Martinez had admitted that it was from her stem cells that had caused paralyzed rats to become fully mobile. Not pleased, Ben informed her how traumatized she had been from the military's constant experiments on her.
Some months later, her grave was violated and her remains stolen by the military, along with all of the other merpeople who had tragically perished in human form, even those of Charles Pownall's half-mermaid daughter. A shocked Ben glimpsed her corpse in a lab of the military.
In "Survivor", Donna appears to Helen as a spirit residing in the Spirit World, the merfolk's version of the afterlife. Helen tries to speak with her about the whereabouts of Sarge's spirit, but Donna disintegrates into ashes before she even spoke. In "Life and Death", she reappears as a flashback in Helen's memory and is mentioned by her to Xander, who still regrets killing her. In "Til Death Do Us Part", her remains and other mermaids were found by Xander and later Ryn, Cami and Helen decided to take them to the water to be buried.
She reappears again when she visits her daughter and the rest of her colony at Caspian Ranch, she tells them that Ryn needs their help in the water.
Ryn is Donna’s mermaid sister and her new leader in their mermaid colony. They share a close relationship, especially after the death of their mother years ago; they also hunt for fish together in the ocean. However, during one of their food hunts, they are caught in Xander’s father’s ship net and beached on their ship. Ryn and Donna try to escape while injuring Chris Mueller in the process. In the end, Donna is captured by the U.S. military and Ryn escapes. Ryn later beaches herself and turns into a human in an attempt to find Donna. After escaping the U.S. military’s clutches, Donna shares a heartfelt reunion with Ryn and they return to the ocean together.
A month after their reunion, Donna and Ryn are forced to find help on land due to humans over-fishing in their waters. Donna goes against Ryn’s friends (Maddie and Ben) after she believes they are the ones responsible for over-fishing in their ocean, which strains her relationship with Ryn. Much to Donna’s dismay, Ryn stays on land to rectify the fishing situation while Donna returns to their mermaid colony in the ocean. After Donna realized her colony wants to kill Ryn for staying on land too long, Donna temporarily abandons the colony and allies with Ryn and her friends to stop their colony. She is even willing to die along with her sister. This restores their close relationship. However, Donna risks losing her life after Xander unintentionally shoots her. Ryn anxiously waits for Donna to recover, but Donna’s chances are slim according to Ben, Maddie and Helen. However, Donna and Ryn are staying side-by-side until they can find a solution for Donna’s recovery. However, when there is no solution, Donna tragically passes away in Ryn’s arms. Her lifeless human form is taken to a secret and sacred resting place for fellow mermaids who were ruthlessly slaughtered while in human form; Ben and Helen's own ancestors.
Katrina was the dominant mermaid of Ryn and Donna's colony. As a result, Donna was very loyal to her, and sincerely believed when Katrina had promised to do everything to bring Ryn back to the ocean.
However, when Donna discovered that Katrina and Levi had the real goal of killing Ryn, she did not hesitate to oppose them, even if that meant they should kill her too.
Donna is Cami's mother. Donna is Cami's mother. However, since Cami lived exclusively with her father, to learn to hunt and survive from her birth, Both mother and daughter were never seen together during the series and we do not know more than that the close mother-daughter relationship they had with each other, that Cami misses her enough to take vengeance upon her unintentional killer.
She was aware and weary of him and ignores his calls for her to stop. He witnessed her painful transformation from human legs to gray mermaid tail. The sight of her true form was enough for Xander to pursue her against his father's wishes and Ben's reluctance.
Aldon is a scientist who experimented on and tortured Donna in a military facility. Donna despises Aldon and even attempted to kill him (with Ryn) as revenge. However, Donna decides to abandon her revenge scheme and return to the ocean due to other issues. Whether or not Donna is aware, Aldon is obsessed with her siren song despite their hostile relationship. When Aldon begs Donna on her deathbed to sing to him one more time, she is barely able to respond and Ryn intervenes by rejecting his request. When Donna dies, Aldon felt he had no other choice but to kill himself.
Donna found shelter with Helen after she argued with and left Ryn to stay with her human friends. Donna was surprised to learn that Helen was also a mermaid, which strengthened their alliance. Donna only had minimal interaction with Helen, until she returned to land and Helen’s store a second time, after Sean McClure’s death. Helen is angry at Donna because she believes Donna was in on Sean’s murder. When Donna’s fellow mermaid colony members attacked Helen after she angrily asked them of their involvement in Sean’s death, Donna saved Helen by stopping Levi and Katrina from killing Helen and the two ran out of Helen’s store. After this and the war between Donna and her colony (which led to Donna being shot), Helen repaid Donna by allowing her to stay in her home to try and recover from a deadly shotgun wound. It can be assumed their relationship is friendly again, especially when Helen allows Ryn to bury Donna’s deceased body where her ancestors were buried.
Donna got off on the wrong foot with Ben (and Maddie) when she met them through Ryn. Donna believed Ben and Maddie were the humans responsible for over-fishing in the ocean and rebelled against them. Donna only worsened her relationship with Ben when she allied with Levi and Katrina against Ben and his friends while on Xander’s ship. Donna was a part of the alliance that killed Sean McClure (Ben’s best friend’s father), but Donna rectified this by siding with Ryn against Levi and Katrina when they all surfaced from the ocean.
Donna recognizes that Ryn shared a connection with Ben, which worried Donna because of her mermaid colony’s strict rules against a mermaid/merman staying on land with a human lover. However, Donna and Ben still allied together to stop Levi and Katrina from killing Ryn. Their alliance only becomes stronger when Ben assists Ryn in taking Donna to safety after Xander unintentionally shoots her. Donna later passes away in the company of Ben, which saddens Ben.
Admiral Harrison & the U.S. Military
Although Donna doesn’t interact with Admiral Harrison that much, he still became her enemy along with the members of the U.S military. Harrison made Aldon Decker treat Donna as a test subject and no more, which angered Donna up until her death and made her assume all humans were bad.
The admiral also made Decker and the rest of his scientists torture and experiment on Donna being she was a mermaid. However, the admiral and Donna don’t interact again once she escaped the military facility she was being held in. Donna is grateful to have escaped the facility and to Ben away from humans, such as Admiral Harrison. Even deceased, she still had great value; enough for her grave to be violated and her corpse to be taken and put in one of their laboratories for further study, even as a decaying corpse.
- She is the first to learn of Helen Hawkins' true identity as a mermaid-human hybrid, even if Ryn could instinctively recognize Helen as one of her kind from their first meeting.
- She is the first mermaid to die in the show, as well as the first dark-skinned mermaid in any mermaid-related show. The other ones were Cami, her daughter, and Viv.
- Her lack of resemblance to Ryn suggests that although sharing the same mother, they would be from two different fathers, which would make them maternal half-sisters.
- She is the first mermaid of Bristol Cove to be killed after the first massacre by Charles Pownall and his shipmates. The second one was Sarge.
- It wasn't until Season 2 that she was revealed to have a daughter, who resembles her enough to be her twin sister and assumes the name "Camden" and is taken to her gravestone.
- It is at her grave site that Ryn and Katrina finally declare a truce in their rivalry and agree to work with Helen, Ben, Maddie and even Xander to save the ocean.