George Clooney didn't have time to play pranks while filming 'The Monuments Men'.
The 52-year-old actor stars as Lieutenant Frank Stokes in the action drama which he also produced and directed, and because of the intensity of his involvement in the film he didn't have time to mess around with most of the A-List cast, but he made an exception for co-star Matt Damon.
Bob Balaban - who stars as Private Preston Savitz alongside the Hollywood legend - told BANG Showbiz at the movie's UK premiere at the Odeon in London's Leicester Square on Tuesday night (11.02.14): "George doesn't have time to play pranks when he's directing and acting in the movie - I don't know how he had time to eat - but he did do one, he pranked Matt Damon. But none of the rest of us had the pleasure of getting embarrassed."
Balaban praised Clooney for his attitude on set and dedication to the film which is based on the true story of a team of soldiers who recovered millions of pieces of artwork stolen by the Nazis in WWII.
He added: "I found him [George] wonderfully self-effacing and interested in doing his job."
Bill Murray, John Goodman, Jean Dujardin and Hugh Bonneville were among the other stars to attend the premiere.

Paolo Nutini treated fans to an exclusive preview of his new album during a secret gig in London last night (11.02.14).
The 'Last Request' hitmaker took to the stage at the tiny Boston Arms in Islington to preview material from his latest record 'Caustic Love', which is released on April 14.
The audience included 400 lucky fans and about 100 journalists, who were given the chance to hear the singer perform his new songs live.
He opened with the lead single 'Scream (Funk My Life Up)', before paying tribute to his mother who had travelled from Scotland to celebrate with her son.
The 27-year-old star introduced his new track 'Looking For Something' at the 70s dancehall and said: "This is a song about my dear mother who is here tonight. I love you mum."
Other tracks including 'Diana', 'Better Man' and 'Looking For Something' had fans dancing transfixed and he continue to thank them for their support, saying: "I appreciate you haven't heard these songs before so thank you for coming to check them out, hopefully you will know them soon so you can sing along."
Paolo also gave fans a retrospective of his greatest hits such as 'Jenny Don't Be Hasty', 'Candy', and 'New Shoes'.
'Caustic Love' is Paolo's third studio album and follows 'Sunny Side Up' in 2009 and 'These Streets' in 2006.
The singer is playing a number of shows to promote his new material in coming weeks, including a gig at the Glasgow Barrowland on March 29.

Damon Albarn will play two intimate London shows to launch his debut solo album.
The Blur frontman, whose record 'Everyday Robots' is set for release on April 28, will perform at the Rivioli Ballroom in Crofton Park on April 30, followed by a show at The People's Palace at The Great Hall at Queen Mary University in London on May 1.
His band will include guitarist Seye, drummer Pauli The PSM, bassist Jeff Wootton and Mike Smith on keyboards.
The singer's new record is co-produced by XL Records boss Richard Russell and features contributions from Brian Eno and Bat For Lashes singer Natasha Khan.
Damon said: "Richard Russell was a fantastic editor and did a lot of the atmospheric stuff, so in a sense it's not entirely my record. It is my narrative, and my voice and my songs."
The singer will also play a number of festivals this year in Belgium and Denmark, along with headlining Latitude in the UK in July.
Meanwhile, Damon will also be honoured with the NME Award For Innovation at this year's NME Awards with Austin, Texas.
He picks up the prize, which recognises him as one of the UK's most influential musicians, on Wednesday, February 26 at the O2 Academy in Brixton.

Damon Albarn's live dates..

April 30 - The Rivoli Ballroom, London
May 1 - The Great Hall at Queen Mary University of London
May 3 - SOS 4.8 Festival, Spain
May 5 - Alhambra, Paris
June 27 - Down The Rabbit Hole Festival, NL
July 3 - Werchter Festival, Belgium
July 4 - Roskilde Festival, Denmark
July 19 - Latitude Festival, UK

Britain's Duchess Catherine attended the Portrait Gala 2014 held at the London's National Portrait Gallery last night (11.02.14).
The 31-year-old royal looked stunning in a full length dark blue Jenny Packham gown with a dazzling silver Nizam of Hyderabad necklace, which was on loan from Queen Elizabeth, as she stepped out of a black car to greet fans.
The dress code for charity fundraiser was "black tie with a hint of sparkle" and Catherine didn't disappoint on her first official royal engagement of 2014.
The pretty brunette, who is married to Prince William, met a number of big names at the event, including celebrated photographer David Bailey, artists Jonathan Yeo, actor Alan Rickman and Olympic Gold medallist Katherine Grainger.
She told guests: "The Gallery's achievements are exceptional. They hold the most extensive collection of portraits in the world, and their unique and brilliant exhibitions never fail to inspire us all."
Catherine also chatted to transvestite potter Grayson Perry, who recently picked up his CBE from Prince Charles at Buckingham Palace, becoming the first man dressed as a woman to do so.
The pair shared a joke after Grayson told the Duchess of Cambridge he was "channelling his inner peeress."
Actress Elizabeth Hurley also attended the event and wore a beautiful gold evening gown.
Catherine, who has recently been busy caring for her seven-month-old son Prince George, was later escorted by Sandy Nairne, the director of the gallery, to view a display of 200 postcards created anonymously for the fundraiser by a selection of famous artists.

'The Paradise' has been axed by BBC bosses.
The department store drama - which was a rival of popular ITV show 'Mr Selfridge' - has been cancelled after two series.
Millions of pounds were spent on the costume drama starred 'Game Of Thrones' actor Emun Elliott as Moray, the owner of a glamorous store, and rising Scottish actress Joanna Vanderham, as a shop assistant and Moray's love interest, Denise.
A BBC spokesman told The Journal: "We are incredibly proud to have made two successful series of period drama The Paradise for BBC One.
"However, in order to make room for new dramas to come through, 'The Paradise' won't be returning."
The show struggled to win over viewers during a battle with 'Mr Selfridge', starring 'Entourage' actor Jeremy Piven as the US entrepreneur who founded the famous London store, despite it being aired four months earlier in September 2012, after producers insisted it had been commissioned first.
Viewing figures were good in the beginning and it launched with around six million for the first series before dipping to just over five million for the second run late last year.
The series was filmed in Lambton Castle in County Durham, which had been converted into a bustling upmarket store, and was the biggest drama ever to be shot in the North East of England.
It also starred Ben Daniels, Sarah Lancashire, Peter Wright, Elaine Cassidy and Matthew McNulty.

Orlando Bloom was seen "getting cosy" with a brunette at a party last week.
The 'Lord of the Rings' actor - who has been romantically linked with actresses Margot Robbie, Nora Arnezeder and Condola Rashad since splitting from wife Miranda Kerr last October - was with a group of friends at New York's Bodega Negra but only had eyes for one female member of the group.
An onlooker told the New York Post newspaper: "Orlando was with friends, but was focused on one American girl, a brunette.
"He was getting cosy with her. He had his hand on her leg, and she was whispering in his ear while they were looking at pictures of his son on his phone."
The 37-year-old actor - who has three-year-old son Flynn with Miranda - was later spotted dancing, though tried to go unnoticed in a large fedora hat.
The source added: "He was breaking it down dancing."
Orlando was also overheard telling pals he is planning to move out of his apartment in trendy Tribeca.
Following their separation after three years of marriage, Orlando and Miranda - who is rumoured to have started dating Australian businessman James Packer - have pledged to remain friends for the sake of their son.

Julia Roberts' half-sister left a "ranting" note which reportedly claimed the actress "drove her" to suicide.
Nancy Motes - who had a difficult relationship with the Oscar-winning star - was found dead on Sunday (09.02.14) and insiders investigating her passing say she "definitely" took her own life.
A source told the New York Daily News newspaper:
"It was definitely a suicide. She left a five-page suicide letter. The EMT found it.
"There were three pages of rantings that her sister drove her to do this. There was one page to her mom, telling her how much she loved her, and one page apologising to [her fiancé John Dilbeck]."
Nancy - the daughter of Julia's mother, Betty Lou, and stepfather, Michael Motes - was found by her fiance in the bathtub of a Los Angeles' house she was pet-sitting at and her body may have lain undiscovered for up to 12 hours.
The source added: "It looks like a pill overdose."
Before her death, Nancy made a series of tweets attacking her famous relative, who she fell out with last summer after giving a tell-all interview.
In one post last month, she wrote: "So my 'sister' said that with all her friends & fans she doesn't need any more love. Just so you all know 'America's Sweetheart' is a B***h!!'(sic)"
And a later tweet read: "Do you want to be a fan of someone so cruel? She's not even that good of an actress. Happy you totally F***ed with me? (sic)"
The messages have now been removed from the social networking site.
Coroner's spokesman Ed Winter confirmed there was a suicide note found but said he didn't believe it ran to eight pages.
An autopsy was completed yesterday (11.02.14), but the cause of death has been deferred until additional toxicology tests are carried out.

Dianna Agron has reportedly split from her boyfriend.
The former 'Glee' actress has been romantically linked to Australian restaurateur Nick Mathers since August last year, but it is believed the blonde beauty "dumped him a month ago", according to E! news.
It is not yet known why the 27-year-old star - who has dated Alex Pettyfer and Sebastian Stan in the past - called time on her brief romance, but it is thought their clashing schedules played a part in their split.
Dianna is currently busy filming for her flick 'Zipper' in Baton Rouge, Louisiana, while Nick has had his hands tied up in his restaurants in New York, Los Angeles and Australia.
When the pair first started dating last summer, a source said their relationship was getting serious quite quickly.
An insider said last September: "It's pretty new, but it's serious. Nick [Mathers] is amazing, from Australia. [He's an] incredible designer [and has] great restaurants like Ruby's Burgers in Australia and NYC, Goldie's and Eveleigh here in LA. He's a really super sweet, lovely guy."

Sandra Bullock was worried about her bum being on show too much when filming 'Gravity'.
The 49-year-old actress, who has been nominated for an Oscar Award for female lead Dr. Ryan Stone in the hit sci-fi movie, made sure she had the best figure possible for the role as many scenes show her from behind.
According to The Sun newspaper, she said: "I worked out hard for this movie, I had to because there is a lot of me on show. I had a few arguments about the scenes where I'm basically in my underwear with pants that don't even cover my bottom!
"I'm flying away from the camera so my butt is in people's faces a lot. I mean, why is that necessary?"
Sandra is also up for Best Actress at the BAFTA Awards 2014 on Sunday, February 16 at London's Royal Opera House.
She is up against Judi Dench, Cate Blanchett, Emma Thompson and Amy Adams in her category at the annual ceremony.
Speaking at the annual Academy Awards Nominees Luncheon in Beverly Hills on Sunday (10.02.14), Sandra also said: "I worked with the nicest, kindest, most patient group of people who all had a tremendous amount riding on them because of new technology, unknown waters.
"It should have been a very stressful situation, but everybody was so supportive that I had one of the best filming experiences I've ever had."

Taylor Swift is planning to scrap a year's worth of songs.
The country pop starlet is planning the follow-up to her highly successful album 'Red' but wants to ditch a lot of the material she has written since the release of her fourth studio album in 2012.
According to the Daily Star, she said: "I basically like to write for about two years before I finish with an album.
"I know whatever I write about at this point is going to get thrown away.
"I'm probably going to like it but it's going to sound a little too much like the last project that I had.
"It's only by the second year in that it ends up sounding like the next project."
"I know whatever I write about at this point is going to get thrown away"
The 24-year-old star has just completed the UK leg of her 'Red' Tour and was joined by Emeli Sandé for a version of 'Next To Me' at London's O2 Arena this week.
The blonde beauty has also sung on stage with Ed Sheeran, BRITs Critics' Choice winner Sam Smith and The Script's Danny O'Donoghue while she's been performing in the city.
Talking about writing her next album, she admits she is suffering from "anxiety", but explained: "You need to challenge yourself and trust your influences. I need to be inspired by different things.
"At this point I feel like staying the same would be the easy way to go but it's not the way that I want to go creatively.
"It's harder to call up people you don't know and work with them for the first time.
"And it's harder to think of topics you haven't covered and think of new ways to say old emotions that everyone feels - but that's the goal."

Paul Barber had to feed parrots for his guest role in 'Death In Paradise' and admits he got quite attached to his feathered co-stars.
The 62-year-old actor - who is famous for playing Denzil in 'Only Fools and Horses' - portrays bird guide Captain Jack in the next episode of the crime comedy/drama and although he was wary of his scenes with the parrots at first he soon grew to like them.
He said: "I play a guy called Captain Jack who is a twitcher guide, you know, a bird watcher. So I'm a local guide in Saint-Marie and I've got a load of twitchers and I'm about to show them where this very rare parrot is - the Saint-Marie Parrot. One of our twitchers gets killed, and then everybody is under suspicion, including Captain Jack.
"I shot a scene with a parrot in my office for Parrot Tours on the island. I've got a couple of parrots in my office and I had to feed them. Funnily enough the parrots were great, I even looked away when I was feeding them. They just gently take the nuts out of your hands, you think, 'It's going to bite my fingers off!' But they gently take the nuts out from between your fingers. I had no problem with my animals and my parrots. I got quite fond of them."
Paul spent two weeks on location in Guadeloupe and he admits shooting the show - which stars Kris Marshall in the lead role as Detective Inspector Humphrey Goodman - felt like a holiday at times because of the stunning Caribbean weather.
He told BANG Showbiz: "It wasn't the hardest job! it was brilliant out there ... I got to spend about two weeks in Guadeloupe, it was like a holiday. I got a couple of days off during filming and it was great to go round the island and go on a little tour. The crew, drivers, the runners everyone was brilliant. With it being an island on your day off, some of the drivers and runners would take you on a trip around the island. It was brilliant."
'Death In Paradise' continues on Tuesday 18 February at 9pm on BBC One.

Natalie Cassidy wants to do the 'EastEnders' cancer storyline justice.
The actress has reprised her role as Sonia Fowler in the BBC One soap and is finding it challenging starring in scenes about her on-screen mother Carol Jackson being diagnosed with the faulty BRCA gene because it brings back memories of her own mum's passing in 2002.
She told OK! magazine: "It has been a really difficult storyline for me, although that report was blown slightly out of proportion. Cancer is sadly something that will touch most of us in our lives in some way, so it's really important we get this storyline right. Hopefully, we will do it justice."
The bubbly brunette - who she played from 1993 to 2007, briefly reprising the part in 2010 and again in 2011 - is loving being back on the Walford set with her old friends and joked she will never leave again.
Natalie enthused: "I love being back. It feels like I've come home. I never want to leave and now I'm with so many old friends again, such as Adam Woodyatt and Steve McFadden - I've known these guys for years."
The 30-year-old actress is especially enjoying the addition of Danny Dyer to the cast, who she says has fitted in perfectly.
Natalie added: "Danny is doing really well. For a long time there have been talks about him joining the show, but nobody knew how he would fit in. But he's come along and slotted in perfectly. He's gone down such a treat with viewers as well."