The party of the so called "ten ferrets" is a group of ten Aes Sedai that were sent back to the White Tower by the Salidar Six rebel leaders as a fifth column. All of them were out of the Tower when Siuan was deposed; they were chosen as this would help reduce suspicion. Apparently, they had returned in response to Elaida's summons of all Aes Sedai.
They have to spy Elaida's activities for the rebel Aes Sedai, and to spread dissent inside the Tower, for example revealing about the Red Ajah's involvement in setting up Logain Ablar as a false Dragon and Elaida do Avriny a'Roihan's knowledge of this plot. [1][2].
The Salidar Six leaders felt that this was one way to prevent sisters from wanting to return to the Tower while, at the same time, destabilizing the Tower from inside and undermining Elaida's position.
Because the Rebel Hall of the Tower was ignorant of this mission, when Egwene knew about it she blackmailed the Salidar Six leaders to give an oath of fidelity to her.
They were two Aes Sedai from each Ajah, save Blue and Red. All of them were discovered by the Black Ajah Hunters, the two Sitters Seaine and Pevara; the first discovered was Zerah Dacan[2] and immediately all of them were captured and forced to sworn an oath of obedience to the Sitters and to help them in the hunt of the Black sisters. The Sitters also make use of them by ordering Meidani to try and re-new a friendship with Elaida.
Since they have sworn on the Oath Rod in front of the Black Ajah Hunters and stated that they are not Black, it is known for certain that none of them are Darkfriends.
When Beonin, who has been spying on the Salidar Aes Sedai, returns to the White Tower, she tells Elaida all about the ferrets. Tarna wants to know if she should have them arrested, but Elaida tells her to simply have them watched, to see who they associate with. She also tells Tarna to have Meidani invited to dinner with her, since she now knows why Meidani has been trying to renew their friendship [3].
When Egwene finds out about Beonin, she orders her to alarm the ferrets about their situation; Egwene then tells Meidani her work is appreciated and advices the Black Ajah Hunters that they should release the ferrets from the outlaw oath of obedience to them, despite the circumstances they were forced to obtain it[4].
They are reluctant at first, but eventually Egwene persuaded the Sitters to remove the ferrets from their oaths, because it was a wrong way to proceed, despite the need of extreme secrecy and security[5].
The ten sisters chosen are all quite strong in the One Power, between level 16(4) and 19(7), high in the hierarchy and able to open a suitable Traveling gateway. The rebel leaders most likely wanted to send influential Aes Sedai to spread dissent against Elaida, rather than simple spies.
List
The ten ferrets in hierarchical order, with their Ajah, strength level and years of training:
- Haesel Lusara, Brown Ajah 16(4) 14
- Ester Stepashin, Green Ajah 16(4) 15
- Bernaile Gelbarn, White Ajah 16(4) 16
- Annharid Matoun, Yellow Ajah 17(5) 14
- Meidani Eschede, Gray Ajah 17(5) 15
- Cathal Devore, Brown Ajah 17(5) 17
- Jennet Cobb, Gray Ajah 18(6) 19
- Mikio Vadere, Green Ajah 18(6) 23
- Celestin Eguilera, Yellow Ajah 19(7) 9
- Zerah Dacan, White Ajah 19(7) 15