The major exceptions are St Catherine's chapel, which was partially rebuilt and given a new window in the early 14th century, and the tower built in 1843.

There is a blocked arch at the end of the north aisle which suggests there was once also a chapel on this side of the chancel.

The mural has been described as "perhaps the most interesting ancient wall-painting in England" and as "one of the most important English wall paintings" of its date.

[2][3] The overall scheme combines several iconographic subjects, including the Last Judgement, the Harrowing of Hell, and the Ladder of Salvation.

The upper half depicts the Harrowing of Hell to the right and the Archangel Michael weighing souls to the left.