Archer and Walker had been serving Camille Belcourt during the times Downworlders were not yet subject to the laws of the Clave, which would have made it illegal. As a human subjugate, Camille frequently fed on Archer, and he was also fed small amounts so he would remain healthy and alive much longer. The presence of their master's blood in his system also kept him docile, and so he continued to serve the master whom he adored.
In 1878, Archer delivered Camille's jeweled brooch and dress provided by Camille to the London Institute for Tessa Gray to use at Alexei de Quincey's party. When Camille left London fearing retribution from de Quincey, she left Archer with her then lover Magnus Bane and he became his unwilling footman. Archer apparently loathed Magnus and disapproved of their relationship because he was a warlock. He also disliked the Nephilim.
Will Herondale often ran into Archer during his frequent visits at Magnus' place, Camille's former residence. Archer was shown to have a dislike for Will because he constantly barged in and pushed past him into Camille's home. Later though, one of Camille's subjugates, most likely Archer, alerted Magnus that Will was at Benedict Lightwood's party, prompting the latter to help Will and Tessa leave.
Years later, Archer and Walker still served Camille. In October 2007, under orders from Camille, they interrupted Simon Lewis's date with Isabelle Lightwood at a diner to let him know that their master wanted to meet with him, referring to Simon as "Daylighter". When Simon agreed, they took him to see Camille Belcourt.
Both Archer and Walker were killed by the Shadowhunters of the New York Institute during a raid to capture Camille. Upon seeing Archer and Walker dead, Camille cried, stating that both had been with her for 200 years and were like her children.
Archer, through his years as a human subjugate, had become almost as pale as a vampire. He was often described as sickly-looking, wrinkled, short, and extremely gaunt. He had pale green eyes and thin, stringy gray hair.