In a press release, the company emphasized that the performance by the retired dancer is a "rare 'gala-only' appearance."
The evening's program also includes the "Diamonds" pas de deux from Balanchine's Jewels, Ulysses Dove's Red Angels, and Balanchine's Symphony in Three Movements.
Boal comes to PNB from New York City Ballet, where he was a principal dancer. He replaces Kent Stowell and Francia Russell, the company's longtime artistic directors, who are credited with transforming the company from an adjunct to the Seattle Opera to a well-regarded company in its own right.
For information and tickets to the gala, go to www.pnb.org.