Sonic Underground

Argus, a captain of the Queen's guard, is captured by Sleet and Dingo before he can reach the secret rendezvous where he was to meet Queen Aleena. While listening to a scanned radio message, Sonic, Manic and Sonia overhear that a queen's guard has been captured and robotisized. The Hedgehogs then begin their pursuit to recapture captain Argus from Robotnik and get the information revealing the secret meeting place where they may be reunited with their beloved mother.