It’s hard to imagine a story much slighter than Sofia Coppola’s Somewhere, a running diary in the life of a Hollywood star – a life rife with malaise, superficial encounters and the occasional, frustratingly inconvenient reminder that he is something more than the sum of his celebrity.

Johnny Marco (Stephen Dorff) is also a dad, just not a very attentive one. Yet when he invites his daughter Cleo (Elle Fanning) over for lunch and a little Guitar Hero, he cares enough about her feelings to kick one of his many anonymous conquests to the curb, at least for the afternoon. Cleo is the first to sign the cast on his arm.

Johnny lives a life most of us know from the tabloids, having assumed apparently permanent residence in West Hollywood’s Chateau Marmont, where there seems to be a party behind every door. He goes through the usual movie-star motions, appearing at press junkets to mouth unrevealing sound bites about his latest movie. “Who is Johnny Marco?” he is asked, and his response, or lack thereof, is telling.

There is plenty of downtime – too much, we suspect – but Johnny doesn’t fill it with booze or drugs, though he’s not a portrait of abstinence, either. By night, he hires pretty blonde twins to dance for him, but he seems more diverted than aroused. At all times, except when he’s with Cleo, he seems like someone looking for something better to do.

Cleo is the key to whatever transformation Johnny undergoes in Somewhere, because she can see past his B.S., and because she represents the most redeeming aspect of his curiously lonely existence. She is permanent, unlike the women, the movies, the publicists feigning delight at his every attention. She makes him real.

Does Johnny want to be real? He does. Life is perpetually sunny at the Chateau, but Johnny wants out. He’s sick of the artifice. Where will he go? What will he do? Somewhere doesn’t tell us, and perhaps it’s not important. His desire to escape may suffice.

Johnny is played likably by Dorff, in an understated performance that relies less on dialogue, of which there is little, than nuance. We get to know him through the subtlety of his expressions, sidelong glances and body language. It is a winning turn. Johnny occupies the screen throughout, and the wrong actor might have made him seem merely impenetrable.

Some will accuse Coppola, who presumably knows this life well, of navel-gazing, and the critique is understandable. Somewhere exists in a world most of us will never know, lamenting celebrity’s unseen drawbacks. But there is poignancy in Johnny’s desire to find meaning in a life of 24-hour entitlement, and to become a father in the truest sense. His is a simple story, simply told, but with considerable charm. It gets the details right.