The second panel is devoted to the Annunciation and Resurrection and, on the reverse side, what is perhaps the most pain-filled and exalted portrayal of the Crucifixion ever realized.
The Annunciation and Resurrection was painted by a world-famous master. 
mnli hypothesis: The Annunciation and Resurrection was painted by a world-famous master.  premise: The second panel is devoted to the Annunciation and Resurrection and, on the reverse side, what is perhaps the most pain-filled and exalted portrayal of the Crucifixion ever realized.