Sonic had his chances... but he didn't even use them. Witch made Amy get over him and move on... Will Sonic get Amy's love back?

Knuckles and Rouge have to team up against Doctor Eggman's plot to take all the Master emerald shards. Along the way Knuckles finds out about why Rouge loves gems so much, and why she says that "There is one special jewel that I have never been able to capture." What is she talking about?