A sketchy and underfocused debut, Rocka Rolla nonetheless begins to delineate the musical territory Judas Priest would explore over the remainder of the decade: frighteningly dark in its effect, tight in its grooves, and capable of expanding to epic song lengths.
On the other hand, Rocka Rolla is also murkier, less precise and powerful in its riff attack, and more blues-based; the stylistic debts to Black Sabbath and Deep Purple are obvious at this juncture, although they would become much less apparent on subsequent releases.
The compositions alternate between short songs and extended suites; some are decent, but overall they don't establish a real direction and tend to plod aimlessly in many of the longer pieces.
Mostly a curiosity for hardcore fans, Rocka Rolla definitely hints at Judas Priest's potential and originality, but doesn't always suggest the quantum leap in vision that would occur with their very next record.