ET with Philadelphia Orchestra live: Will it be out of this world?

The Philadelphia Orchestra will be warned: In this week's concert performances of E.T. The Extra-Terrestrial, principal guest conductor Stéphane Denève may well be reduced to weeping. But so might others in the orchestra.

Even Italian opera doesn't tug harder at the heartstrings than Steven Spielberg's classic 1982 film about a boy and his lost space alien, which will be presented with the Philadelphia Orchestra playing the Oscar-winning John Williams score Friday through Sunday at the Kimmel Center's Verizon Hall.

"I have to confess, it gets me each time," Denève said this week. "When I first saw the film, I was myself almost exactly the age of Elliott [a leading character in the movie]. It was the first time I cried in a movie theater. I was embarrassed. It was a new thing to have such empathy for those characters. It was cathartic."

In ages past, symphony conductors were told not to even smile at their musicians in order to maintain their authority. But this isn't ages past.

In fact, Philadelphia is catching up with a national trend: Even the best symphony orchestras play live movie accompaniments, not just in a series of excerpts, but entire films, and during their regular seasons. Though such events are common at the summertime Mann Center, the regular Verizon Hall season has hosted films intermittently, and with high-pedigree titles like Alexander Nevsky with music by Prokofiev, West Side Story with Leonard Bernstein's songs, and Walt Disney's Fantasia, which originally featured a Philadelphia Orchestra sound track.

E.T. is the first of three highly commercial hits to be done in concert this season, followed by Home Alone Dec. 20-22 and Raiders of the Lost Ark March 17-19. Hits obviously have a built-in audience, especially as the concert events promise a truly wide screen (32 feet) and enveloping sound (two banks of 14 speakers) not found in multiplexes. The audience is different from the usual; symphony orchestras love that.

"Most management companies now have a film division," says Jeremy Rothman, orchestra vice president of artistic planning. And each has a specialty: Steve A. Linder, producer of the E.T. event at the Kimmel, with Spielberg/Williams films; John Goberman (who first presented Alexander Nevsky in 1987) with older classics. Films scored by great composers are obvious choices: London's Southbank Centre recently announced Taxi Driver, Bernard Herrmann's last score.

"Some purists may say that it's detrimental to the core repertoire. I believe that it's a new part of the repertoire," says Denève, "though only a few scores really deserve to be played this way. Sometimes if the music is too gimmicky or simple, you're bored in two minutes."

Indeed, the marriage between symphony orchestra and film has to be an artistically happy one, says Linder, producer of Film Concerts Live, the IMG Artists-affiliated company that now has six films making the symphonic rounds. "It has to be compelling music, something meaningful to the audience but also meaningful to the orchestra," he said. "We're very careful what we pick and choose to produce."

The long stretches of music and big orchestral gestures of E.T. would showcase the Philadelphia sound, though much more than that is going on.

"I had a chance to visit John in his home, where he showed me the cue sheets for the score . . . and it had written descriptions, almost second by second, like, 'E.T. turns to Elliott.' 'Elliott turns back to E.T.,'" says Denève. "It's fascinating how he could signal a change with just a little harmonic or rhythmic change."

In symphonic circles, the score also has a reputation for being a harp concerto in disguise. Though the orchestra's principal harpist, Elizabeth Hainen, is usually in the rear of the orchestra, Denève hopes to have her front and center to make sure her key role in the piece isn't lost. In any case, the orchestra has selective electronic sound boosting to ensure good balance with the film.

But the relationship between film and symphony is never seamless. In planning matters, the two worlds are in different time zones: Orchestras sometimes work three years into the future. Linder is still settling a film concert date coming up in December.

Some films are licensed in a fairly narrow window of time, as short as 18 months. Disney takes films in and out of circulation so as not to compete with parallel presentations by, say, Disney on Ice. If a movie remake is in the wind, the original may be taken out of circulation. So orchestras have learned to be nimble. Some film lengths push orchestras into expensive overtime. Linder predicts Gone With the Wind may never make it to the live-orchestra stage.

Most modern films have a music track that's easily dropped from the film to make way for the live symphonic performance. But not always. West Side Story, which made the rounds four years ago (including Philadelphia) had to have the music track painstakingly removed digitally. Orchestrations need adjusting for the sake of practicality.

Though a dozen or fewer specialized stagehands are needed to hang speakers and screen in Verizon Hall, technical director Mike Runice demonstrates how the technology fits into two suitcases, without so much as a DVD, because movies now exist on digital files.

That's partly what attracts a conductor of Denève's reputation to such projects: The quality keeps getting better. But Denève's devotion to E.T. and John Williams in general is also extraordinary. He paved the way for the current three-film season with last spring's Williams festival featuring concert works, film music excerpts, and an appearance by the 80-something composer himself. Williams was reportedly charmed and impressed. So devoted is Denève to E.T. that he hasn't permitted his 8-year-old daughter, Alma, to see the film until these forthcoming Philadelphia performances.

"She will miss school for the rest of the week, but I wanted her to see her very first E.T. with her dad conducting," he said. "It's probably more meaningful for me than for her. I pray she will love the film that was so special for me."

He also knows the new audiences attracted to the film presentation won't necessarily beat down the door for his purely symphonic concerts with the Philadelphia Orchestra. "I'm not stupid," he said, "but maybe some will."

"E.T. the Extra-Terrestrial": 7 p.m. Friday and Saturday and 2 p.m. Sunday at the Kimmel Center, Broad and South Streets. Information: 215-893-1999 or www.philorch.org.

dstearns@phillynews.com