The plaque measures just 0.47 metres wide and 0.6 metres tall, yet within that compact space a carver has arranged three figures in finely worked relief, framed by a cut-stone limestone surround and a raised moulded edge. It sits in a recess to the north of the mullioned window of the south transept, at roughly eye level, where it has been weathering quietly for four centuries.

The central figure is Christ on the cross, bearded and long-haired, wearing a loin cloth knotted at one side and a twisted crown of thorns. His hands, notably large in proportion to the rest of the figure, are each fixed by a square-headed nail; his crossed feet by a single one. To his left, shown in profile and looking upward with hands outstretched toward the cross, stands Mary, his mother, her disk-like halo resting flat against her head and a cloak drawn over a long robe. The figure on the opposite side presents a more ambiguous case. Tall, broad-faced, beardless and long-haired, with arms folded across the chest and gaze directed outward rather than toward Christ, the identity is not immediately obvious. The posture, however, points toward St John the Evangelist: crossed arms are a recognised convention in medieval representations of John, as opposed to the more expressive gestures typically associated with Mary Magdalene. Above the scene, the letters INRI are carved in relief within the moulded frame; below it, the date 1625 confirms this as an early seventeenth-century work, produced during a period when Catholic devotional art in Ireland was being made and displayed under considerable political pressure. A second crucifixion plaque exists at the same church, positioned above the west doorway, making Turlough an unusually rich site for this particular form of carved stonework.