Nico Muhly had just selected his aisle seat for a flight to the Twin Cities when a reporter called Tuesday afternoon.

"You have to get those aisle seats fast," said the New York-based composer, who will fly in for the world premiere of "Luminous Body" on Friday at the Ordway Center for the Performing Arts in St. Paul.

Muhly, on the cusp of his 30th birthday, continues an upward career trajectory that keeps him busy around the world. He was in London this summer for the premiere of his first opera. He was there in 2010 for a song cycle he wrote for tenor Mark Padmore and violinist Pekka Kuusisto. He's written movie scores (including "The Reader") and worked with Björk and the American Ballet Theater. In between, he blogs avidly (at nicomuhly.com) about his music, his process and politics.

"I had a crazy thing where I got back from London and immediately flew to Iceland and then flew home, and all the while, this debt ceiling thing has been raging," he wrote in one post last month. "I got kind of obsessed with it."

And now, he'll be on the aisle in St. Paul to hear the opening of this vocal/instrumental collaboration between the St. Paul Chamber Orchestra and Cantus.

Muhly and writer Craig Lucas created "Luminous Body" on a commission from the SPCO, Cantus and the Minnesota Commissioning Club. It is a key part of the orchestra's season-opening weekend and one more sign that Muhly's rise has put him in a spot where he can pick and choose his commissions.

"Luminous Body" appealed because he knows well the work of Cantus -- having bought its discs for years -- and recognizes the SPCO as one of the better small orchestras in the country.

"I've heard a lot of bootleg recordings of [the SPCO], which I maybe shouldn't admit to you," he said. "They seem the right combination."

The project also gave him and Lucas a chance to shift gears lyrically and musically after the intense and propulsive opera "Two Boys," which Bartlett Sher directed at the English National Opera in June. This new work downshifts, using religious texts such as the Gnostic gospels and the Zohar in a reflective yet chaotic ripple of layers.

"You have these ecstatic conversations, all being spoken at the same time, coming together," Muhly said. "It's very anti-narrative, which for me is what an oratorio wants to be. It's kind of like if everyone in 'Elijah' were speaking at the same time."

Muhly, however, does not consider "Luminous Body" an oratorio. Neither does Aaron Humble, who sings tenor in Cantus.

"There are snippets of solo, big chorus parts, duets, trios, trios that become quintets," Humble said. "There are also interesting pairings of voices with instruments."

You know the name

Twin Cities audiences have some familiarity with Muhly. As a pianist, he performed his work at the Southern Theater in the spring of 2009 and 2010, both times working with violist Nadia Sirota. Last April, his compositions were a centerpiece of the String Theory festival at the Southern, which Muhly describes as "one of those magical places."

"It seemed like the audiences were always surprisingly mixed," he said. "Young and old, some who clearly came all the time and some who didn't. That was a treat, and the space is amazing."

Humble describes Muhly's music as innovative and tuneful -- mixing sweet tonalities and prickly abstraction within the same piece. He also says the composer is especially generous to singers, with modulations and key changes that do "exactly what your ear expects the tune to do."

That comes from Muhly's fascination with English choral music. He joined a church choir as a youngster -- much to the horror of his mother, artist Bunny Harvey -- and the liturgical tradition remains a thread in his work. But with "Luminous Body," he consciously tried to turn the other way.

"A lot of my musical DNA comes from Renaissance or 16th-century music," said Muhly, who has a degree in English literature from Columbia and a master's in music from Juilliard. "There's a way when you have nine male voices [Cantus] to fall too easily into that texture, so I resisted it in this. The piece is very austere."

A celebrated writer

Playwright Lucas has been nominated for a Pulitzer ("Prelude to a Kiss" and "The Dying Gaul") and for a Tony (the book of "The Light in the Piazza"). He has a long history with the Twin Cities, particularly the Playwrights' Center in Minneapolis, where he developed the off-Broadway hit "Small Tragedy" with Hidden Theater in 2003.

Muhly said the two clicked immediately as they went about their business with the opera "Two Boys."

"He thinks and works incredibly quickly," Muhly said of his collaborator. "We can have an elaborate conversation about a tiny thing, like what vowels we need in a line, and neither of us feels like we're being protective of our work; we're doing what's best for the piece."

Humble said he will be curious to hear how Muhly's work will sound with the SPCO instruments.

"Will it lay under their fingers as nicely as it does on our voices?" he asked.

In addition to the new Muhly-Lucas collaboration, the SPCO season opener includes Haydn's Sinfonia Concertante in B-flat for oboe, bassoon, violin, cello and orchestra; Bach's Double Violin Concerto in D Minor, and Brahms' "Variations on a Theme of Joseph Haydn."