Here's a long navy blue prom dress that is as sophisticated as it is sparkly. With a silvery beaded design from the deep v-neckline to the hem, this long beaded formal dress flatters the curves while shimmering under the lights at prom, galas, and other black-tie events. Offered in misses and some plus sizes, this gorgeous long evening gown has thin shoulder straps that lead to the deep v-back, while the hip-hugging long skirt has a side slit that adds a sexy vibe. At under $200, this long navy blue prom dress offers an impressive look at a reasonable price.