The Duke of Buckingham, nephew of the late Henry Stafford, was at home in Brecon Castle when the messenger came from his Auntie Margaret. He was taken aback by her instructions. He must pledge his unconditional support to the Duke of Gloucester as Lord Protector and do his utmost to nullify the influence of the Woodvilles. His immediate reaction was to question his fitness for the role, given that he was married to Elizabeth's sister Katherine! Surely he would be marked as a Woodville sympathiser? Margaret had covered this eventuality. The messenger explained that all he needed to do was complain bitterly about his in-laws, especially about being forced to marry someone so far beneath his own station. The Woodvilles were sufficiently unpopular that no one would doubt his sincerity. The messenger also assured him that John Morton, Bishop of Ely, would give him all the assistance he needed at court in London.
Support duly pledged, Buckingham set out with his men from south Wales to join up with Gloucester, who was heading for London from the north. Young Edward V was also travelling towards London, from near the border with north Wales, in the company of Elizabeth's brother Earl Rivers, her son Richard Grey and chamberlain Thomas Vaughan. The three parties met in Northamptonshire and shared a pleasant evening meal. Before morning dawned, however, the silver-tongued Buckingham had persuaded Gloucester that the Woodville party posed a threat. At daybreak, Rivers, Grey and Vaughan were arrested and dispatched to Pontefract Castle. Edward was distraught at this treatment of his life-long guardians. Gloucester did his best to console his tearful nephew, deceived by the age-old canard that a twelve year old is too young to understand.
On hearing news of the arrests, Elizabeth took the precaution of seeking sanctuary in Westminster Abbey with her children.
Lady Margaret Beaufort was off to a flying start. With Elizabeth in fear of her life, she sent her physician Doctor Lewis to the Abbey to make an offer that ought not to be refused. Her next target would be the pillar of the Yorkist cause, Lord Hastings.