Margaret "Madge" Shelton is a distant cousin and handmaiden to Anne Boleyn while the latter was Queen. A rather dimwitted girl, Madge is initially pressed into service by Anne as a potential (trustworthy) mistress for King Henry while Anne is pregnant.
Madge is introduced among some of Anne's other handmaidens (2.04). Anne, who is pregnant for the second time and trying to rest, is irritated with her ladies for giggling while reading over poetry by Anne's former lover Thomas Wyatt. Anne chastises Madge for her silly behavior and sharply tells her that she should focus more on her Protestant piety, such as reading scripture.
Anne, meanwhile, is preoccupied with Henry's affairs: she is deathly afraid that he will take another mistress, as he did while she was pregnant with Elizabeth. She vents her frustration to her father, who tells her that it is natural for a man to take another woman whilst his wife is big with child. He tells Anne that she should pick a mistress of her choosing, someone who can be trusted by the family. Anne considers Madge as a candidate, considering her shared faith (Madge is also a Protestant), non-ambitious and relatively dim-witted behavior. Anne eventually puts the matter to Madge directly who is bewildered by the offer from her cousin, but nonetheless accepts; Anne later presents her to Henry, who is intrigued.
Some days later, when Anne is feeling unwell, she offers for Henry to take Madge on a ride with him instead; Anne cries in pain as Henry and Madge set off, unhappy that he still chooses to be unfaithful. The pair spend the rest of the day and night drinking, culminating in a heated affair.
Madge calls the physician when Anne suddenly begins bleeding and collapses, but her child is nonetheless stillborn (2.05).
After the miscarriage, Anne's behavior (which has gradually become more and more erratic since episode 2.06) makes Madge suspect she may be unfaithful to Henry (2.08). She spies as Anne embraces with her brother George and her friend Mark Smeaton. Perhaps also jealous of Anne's position or angry at her for pushing her into sleeping with Henry, Madge makes friends with Anne's rival, Jane Seymour, when she becomes Anne's maid, hoping to spite her.Madge, however, is still horrified when Anne miscarries Henry's son (2.08).As Henry begins to believe that his marriage to Anne is cursed by God, rumors spread of her possible infidelity, and Madge is brought to Thomas Cromwell for questioning (2.09). Frightened of being associated with Anne, who has lost all favor with Henry, Madge hastily gives Cromwell circumstantial evidence that makes Anne look guilty of adultery, incest and even witchcraft. She is later present when Anne is arrested and weeps, perhaps feeling guilty for turning in her cousin.
Madge is not seen in any further episodes; presumably, due to her association with the Boleyns, her family were banished from court.
Margaret and Mary Shelton were sisters, although historians today believe they are the same person (the confusion coming for a portrait, where the "y" in Mary was confused with a "g"). Unlike the series, the Shelton sister or sisters did not give evidence against Anne Boleyn. One of the Shelton sisters is believed to have been King Henry's mistress for a six-month period beginning in February 1535, according to statements about mistresses made by the Imperial ambassador, Eustace Chapuys, who referred to Mistress Shelton.