When most artists reach the age of 76, they tend to lower their aims. Riding on the coattails of their creative heyday is an easy way out for many older musicians. But Wayne Shorter, after a half century in jazz, proved to be just as wily, creative and restless as ever during his concert for Cal Performances on Saturday.

Shorter has always been an innovator. He has explored the outer limits of acoustic jazz, penned marvelously unique compositions (many of which are now standards) and helped forge into electric territory as a founding member of jazz-fusion group Weather Report. So it was only fitting that Saturday's set, featuring the outstanding trio of pianist Danilo Perez, bassist John Patitucci and drummer Brian Blade, was just as forward-looking as anything Shorter has done.

It's hard to describe the music the band played because it challenged nearly every major assumption in jazz. Throughout their nearly two-hour set, the group played merely two songs. A brief encore rounded out the night, but otherwise the set was dominated by extended, unpredictably shape-shifting compositions. There were no repetitive cycle of "changes," no 32-measure long chord progression for the soloist to blow on.

In fact, there never truly were any "solos." Occasionally, one musician would play more prominently than the others, but overall, the band improvised collectively. Though ostensibly the leader, Shorter played the least of the four. Judging from the thick scores the musicians kept thumbing through, Shorter probably acted more as a composer than a frontline player. When he was playing, his lines came in short bursts and usually highlighted things other musicians played. For most of the night, he leaned into the curvature of Perez's grand piano, coolly absorbing the sounds emanating from his spectacular band. The group listened to each other like few bands do. Every note they played was an attempt to bolster the whole, not to attract attention toward any one musician.

Shorter expanded the boundaries of what sounds constitute music. In addition to constantly alternating between tenor and soprano, he employed many unusual sonic techniques. He whistled, panned his sax away from the mic and dropped objects into the piano's body, producing random percussive noises.

Shorter's intrepid band followed him in exploring outside-the-box technical approaches to their instruments. Perez slammed the piano's keyboard cover shut and used his elbows and knees to hit notes. In the opening bars of the first tune, he reached inside the piano's body to strum its strings by hand, creating a lush wave of tinny reverberation. John Patitucci bowed and strummed his bass, alternating between funky angularity and melodic clarity.

Brian Blade never really "kept time." Rather, he played complicated patterns that contrasted with the pulses implied by the group. Rarely has any drummer shown such extraordinary dynamic range. With brushes, mallets and his bare hands, he played scarcely above a whisper. With sticks, he thundered bombastically on his set in a way that really heightened the drama.

The Wayne Shorter Quartet's performance two nights ago lived up to Shorter's maverick reputation. It called into question many common assumptions and pushed the boundaries of what is possible in jazz. Listening to these compositions was like watching a cloud drift across the sky, morphing into strange and unexpected shapes. Whenever the music ballooned into heated, fiery cacophony, it would always land comfortably back down in calm meadows of melodic tranquility. It had a near classical focus on dynamics, texture, color and musical storytelling. Though it's hard to tell exactly what new territory Shorter and his band are forging into, it's impossible not to want to hear more of whatever it is.