The Lady Chapel has a marble altar that was once part of the High Altar. It was designed by James Wyatt at the same time as he restored the reredos in 1789. He was responsible for most of the interior decorations of the mansion house after Joseph Damer had sacked his second architect, Sir William Chambers. To the left of the altar is a picture John Tregonwell (V), who at the age of just 5 years old fell from the roof of the Abbey in 1605, but was saved by his voluminous pillowing petticoats, which acted like a parachute.
On the left side, behind the sedilia, there is a stone effigy of St James of Compostella, who is the patron saint of pilgrims.
Above a coloured, but defaced niche at the rear of the chapel on the left, is Abbot William Middleton's rebus. It shows a mill over a cask or 'tun', hence 'Milton'.