Watch Once Upon a Prince (2018) HD Full Movie Free on solarmovie.do. Watch Once Upon a Prince (2018) online free. A prince visiting the U.S. falls for a commoner when he helps her. But his mother isn't pleased with...A prince visiting the U.S. falls for a commoner when he helps her. But his mother isn't pleased with the match and tries to prove that the American gal isn't suitable to be a royal bride.