Few companies truly perfect the delicate balance between classical ballet and modern dance. Somehow the San Francisco-based Alonzo King’s LINES Ballet accomplishes just that with enough elegance, conviction and pure artistic genius to lead you to believe that groundbreaking choreographer Alonzo King not only accomplishes it, he defines it.

On Tuesday night, King unveiled his newest creation, “Before the Blues,” to a sell-out crowd in Campbell Hall. The piece, set to an original jazz score by Pharaoh Sanders and narrative recording by renowned actor Danny Glover, opens against a backdrop of the Mississippi River, sunshine glistening off its surface while the lonely notes of a saxophone reverberate through the air of an empty stage. Touches of the South emerge frequently in “Before the Blues,” juxtaposing sizzling heat with the languid nonchalance of a late Georgia afternoon.

One segment features a trio of female dancers, all donning disheveled cream-colored tutus, moving to alternating sequences of King’s signature fusion of classical technique and contemporary innovation. Gifted with extensions that should defy human capability, dancers Laurel Keen, Drew Jacoby and Lauren each demonstrate exquisite fluidity and poise throughout, their bodies rippling like waves of heat while moving through space with nymph-like ethereality.

A later pas de deux showcases two dancers and the awkward but irresistible struggle between union and separation. The haunting repetition of Glover’s voice uttering the words, “Forgive me,” coupled with the intense, seemingly magnetic forces keeping the duo together, absolutely explode onstage, taking the audience through the sometimes excruciating pain of being unable to let go.

The company works remarkably as a whole, each dancer impeccably trained in the foundations of both ballet and modern dance. But it is everything in between, the stylistic choices, the nuances, the indescribable aura that emanates from each of King’s extraordinary artists, that makes this company a standard of excellence in American dance.