At Belmont, Portia has no lack of suitors. Her father, however, has left a will stipulating each suitor to choose one of three caskets: one each of gold, silver, and lead. In order to be granted an opportunity to marry Portia, each man must agree in advance to live out his life as a bachelor were he to select wrongly. The suitor who correctly looks past the outward appearance of the caskets will find Portia's portrait inside and win her hand. Bassanio makes the correct choice, that of the leaden casket.
