Meer Campbell was a woman hired by ZAFT Chairman Gilbert Durandal to posed as Lacus Clyne. He used her to preach his ideals as Lacus has a profound effect on the people of the world.
Gilbert Durandal, the current chairman of ZAFT, realized that Lacus Clyne possessed a very large political influence that was greater then his. He used Meer as his political puppet to gain a large amount of support amung the populace of politices. Meer face and body are surgically altered to be Lacus double. Most people are unable to tell the differences other then Athrun, Kira and most of the other people in the CF can tell that she is not the real Lacus Clyne.
After the Operation Angel Down, Meer overheard Gilbert and Rey talking about Athrun who had been charged with the supposed killing of the Archangel and Freedom pilot, Meer feared that Athrun would be framed as a traitor she went and warn Athrun and tried to get him to spend more time around the Destiny suit to again back the trust he had lost from Gilbert however Athrun made a break for it and encouraged her to come with him. Meer refused the offer as she had become so mentally unbalanced that she believed that she was Lacus.
After ZAFT's attack on Orb Meer interrups Cagalli Yula Athha's broadcast protesting against Durandal's policies to denouces Orb for hiding Lord Djibril shortly afterwards Meer's broadcast was cut off by the real Lacus Clyne, who denounces both Djibril and Durandal. This however creates controversy over woh the real Lacus is.On ZAFT's side many think and believe that Orb's Lacus is merely a fake to confuse them.
After the following events Durandal sends Meer in hiding with her bodyguard Sarah until this have setteled down.He sends them to the lunar city of Copernicus. The Archangel has landed on Copernicus with the real Lacus. Sarah informs Meer that Archangel is on Copernicus to and tells other that the other may be there with them.She tells Meer to do something about it. As Athrun, Kira, Lacus and Meyrin go shopping in the city Meer's red Haro shows up holding a note for Lacus saying that Meer is going to killed.Athrun is wary and thinks it's trap on other hand Lacus and Kira go anways since Meer has claimed for Lacuse help and not KIra's or Athrun.
Meer meets with them in a aboundened amphitheater which is surrened by armed men.Meer clings her own beliefs that she is the real Lacus Clyne. Lacus trys to calm her down and tells her she is her own person with her own dreams,even if she sounds and looks like Lacus. Desperately Meer threatens to shot Lacus but is pervented by Athrun who shots the gun out of her hands.Lacus enters the view of Sarah Meer's bodyguard who is lying and waiting.Torii appers and alerts Kira and Athrun about the threat. A firefight starts as Athrun mangaes to take down most of the armed men and seriously injure Sarah with a grenade deflected by Kira and Meyrin.
Neo Roanoke arrives after the firefight to evacuate KIra and everyone else including Meer.As Lacus is getting ready to climb in the Roanoke hand Kira offers Meer to come with them and she accepts however Sarah struggles to get one more shot at Lacus.Meer decsides to take the shot while Athrun and Kira shoot at Sarah resulting in killing her. As Meer dies she gives Lacus a picture of the real her before she was altered to look like Lacus Clyne after she says sorry to Lacus for what she done Meer asks them not to forget her songs and life and dies in Lacus arms. Later Lacus reads Meer's diary telling her about Meer's life before her surgery.She soon becomes angery at Durandal during his announment of the destiny plan.
Meer is more ditzy and energetic she often tends to get excitiable as well acts a bit childish at times when ever she around or near Athrun.On the other hand Meer appers to be smarter then she looks such as when she bails Athrun out of FAITH.Meer as taken Lacus image as a pop star a but futher then Lacus did such as more dancing and breast augmentation,however all this fame went to Meer head likely messing up her mental sanity proof of that is when Athrun try to get her to esacape. She refused and claimed she was lacus as well she preffered to be Lacus.