preserved preparatory sketches, in which the apostles are clearly labeled by name, there still remains some small debate about a few identities in the final arrangement. But there can be no mistaking Judas, small and dark, his hand calmly reaching forward to the bread, isolated from the terrible confusion that has taken the hearts of the others. One critic, Frederick Hartt, offers an elegantly terse explanation for why the composition works: it combines "dramatic confusion" with "mathematical order." Certainly, the amazingly skillful and unobtrusive repetition of threes—in the windows, in the grouping of the figures, and in their placement—adds a mystical aspect to what at first seems simply the perfect observation of spontaneous human gesture.
Reservations are required to view the work. Viewings are in 15-minute, timed-entry slots, and visitors must arrive 15 minutes before their assigned time in order not to lose their place. Reservations can be made by phone or online; it is worthwhile to call, as a number of tickets are set aside for phone reservations. Call at least three weeks ahead if you want a Saturday slot, two weeks for a weekday slot. The telephone reservation office is open Monday–Saturday 8–6:30. Operators do speak English, though not fluently, and to reach one you must wait for the Italian introduction to finish and then press "2." However, you can sometimes get tickets from one day to the next. Some city bus tours include a visit in their regular circuit, which may be a good option.
The painting was executed in what was the order's refectory, which is now referred to as the Cenacolo Vinciano. Take a moment to visit Santa Maria delle Grazie itself. It's a handsome, completely restored church, with a fine dome, which Bramante added along with a cloister about the time that Leonardo was commissioned to paint The Last Supper.