Night off from Charlize! Sean Penn is dressed down in his cowboy boots to rock out at U2 concert as girlfriend Theron is not seen

After several months of being nearly inseparable, Sean Penn seems to have taken a night off from girlfriend Charlize Theron.

The 54-year-old actor was spotted waiting in line for a secret U2 show at The Roxy in Los Angeles on Thursday evening.

The Mystic River star was surrounded by men as he stood outside the venue.

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Made for walkin': Sean Penn casually wore cowboy boots as he waited in line for the U2 show at The Roxy in Los Angeles Thursday night

Made for walkin': Sean Penn casually wore cowboy boots as he waited in line for the U2 show at The Roxy in Los Angeles Thursday night

The Fast Times At Ridgemont High star wore a vintage-looking olive green jacket, made popular today by brands like Member's Only.

The Oscar winner also wore casual khakis as he stood beneath the fluorescent lights of the marquee.

And to top the look off, the Fair Game actor wore a pair of suede cowboy boots.

Casual: The Mystic River star wore an olive green jacket and khakis as he was about to enter the venue

Casual: The Mystic River star wore an olive green jacket and khakis as he was about to enter the venue

Happy couple: Penn, 54, and Theron, 39, at the Cannes Film Festival premier of Mad Max: Fury Road in May

Happy couple: Penn, 54, and Theron, 39, at the Cannes Film Festival premier of Mad Max: Fury Road in May

Penn has been dating the South African Charlize Theron, 39, since June 2014.

Prior to the Mad Max: Fury Road star, Penn had been married to House of Cards star Robin Wright and pop icon Madonna. With Wright, the star had two children.

But his latest love interest, Theron, was nowhere to be seen as he stepped out for the U2 show.

Bad to the Bono: Reports say that lead singer Bono crowd surfed during the hit Vertigo

Bad to the Bono: Reports say that lead singer Bono crowd surfed during the hit Vertigo

The Irish rock band played the intimate show for a crowd of just 500.

Also in attendance were stars Jack Nicholson, Aaron Paul, Danny DeVito and Courtney Love. 

Reports say that lead singer Bono crowd surfed during the hit Vertigo.

Ready to rock: Breaking Bad's Aaron Paul, 35, looked like he was in a rush to get into The Roxy

Ready to rock: Breaking Bad's Aaron Paul, 35, looked like he was in a rush to get into The Roxy

Happy Jack: Jack Nicholson, 78, was also in attendance for the show

Happy Jack: Jack Nicholson, 78, was also in attendance for the show

Theron and Penn had known each other for years but they didn't start dating until 2014.

Late last year, a source told UsWeekly the couple had become engaged while vacationing in Paris.

'There's no ring,' said the source, 'but they are committed.'

Art chic: The happy couple at The Metropolitan Museum of Art 2014 Costume Institute Benefit Gala

Art chic: The happy couple at The Metropolitan Museum of Art 2014 Costume Institute Benefit Gala

Theron recently starred as badass Furiosa in Mad Max: Fury Road. The couple was spotted at the film's premiere at Cannes Film Festival in May.

Penn's most recent acting credit was as the gun-toting Terrier in The Gunman. The actor is also credited as working on the screenplay for the film.

As his latest gig, Penn has been focusing on directing. His film The Last Face, which stars Theron and Javier Bardem, is due out later this year.

Fashion fans: The duo spotted at the Christian Dior show as part of Paris Fashion Week 2014

Fashion fans: The duo spotted at the Christian Dior show as part of Paris Fashion Week 2014

Giving back: Penn, founder and CEO of J/P Haitian Relief Organization, with Theron at the fourth annual Sean Penn & Friends HELP HAITI HOME Gala on in LA in January 

Giving back: Penn, founder and CEO of J/P Haitian Relief Organization, with Theron at the fourth annual Sean Penn & Friends HELP HAITI HOME Gala on in LA in January 

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