We arrived without any real expectations. Beijing’s prosaically named State Production Base of China Film Group isn’t considered China’s Hollywood; that mantle is usually taken by Hengdian World Studios in Zhejiang province (the world’s largest set of outdoor film studios, over six times the size of its Beijing cousin). Still, bymidday our hopes of celeb-spotting had been raised.

We’d been promised a chance of seeing Canto legend Andy Lau shooting his latest flick alongside Taiwanese bombshell Lin Chi-ling. An hour later, we would leave star-struck after coming face to face (well practically) with a fully-fledged A-list Hollywood celebrity.

The trip had started unglamorously enough: after an hour-long bus ride through the dried-out countryside of Huairou, we arrived at a huge, grey, monotonous-looking building that screamed ‘State Enterprise’. The entrance was guarded by a bronze statue of the China Film Group’s logo – three men in workers’ uniforms, one holding a sickle – suggesting it was from the Soviet era. Actually, it was opened to much fanfare in 2008 and cost 20 million RMB to build.

These are busy working studios, where over 150 films fake oakleys, 100 television shows and myriad adverts are produced each year. Understandably, most of the lots aren’t open to the public, but on our way to the two that are – numbers six and seven – we passed the elaborate wooden boat used in last year’s propaganda flick Beginning of the Great Revival (aka The Founding of a Party).

Lot Six holds the star attraction: the noodle shop from A Woman, a Gun and a Noodle Shop (aka A Simple Noodle Story), Zhang Yimou’s black comedy, set in an imperial China backwater and based on the Coen brothers’ Blood Simple. For those who’ve watched this highly stylised, swashbuckling tale, it’s a treat to reimagine the colourful scenes as you explore the shop set.

On the counter, we found chopsticks with their tops missing and recalled the opening scene, where a Persian merchant slices them off with his sword. Then we posed by the leftover giant noodle bowls. It was at this point that our po-faced guide – who’d gone out of his way to be as stiff as possible, answering questions about which stars were sexiest in the flesh with responses like ‘They are all equal in our eyes’ – let slip that Andy Lau was on the premises.

Out of the 19th-century shop and back into 21st-century Huairou, we kept our eyes peeled. By Lot Eight, a sign showed promise: ‘No mobile phones on set. 50RMB fine’. A moment later, we had to double take: walking past a slightly ajar door, we glimpsed none other than Keanu Reeves in jeans and sweatshirt, lifting an enormous pair of dumbbells. Giggling girlishly, we resolved to go back and speak to him. But on returning, we found Reeves mid-benchpress, legs spread and crotch pointed in our direction. It felt wrong to approach a man in such a vulnerable state.

Instead we caught up with Jeremy Marinas, a stuntman in films such as The Green Hornet and Sherlock Holmes, who was here alongside Reeves. ‘Yeah, I wouldn’t go in there. Keanu is kind of a private guy,’ Marinas warned us, explaining they were shooting Reeves’s directorial debut, Man of Tai Chi, a martial arts movie out next year. They’d been refilming the same fight scene for four days. No wonder Reeves needed to let off a little steam between takes.

Of course, not every visitor is guaranteed any stargazing. The tour of the inside studios alone might leave some disappointed. Only a few small sets remain, including some from 2009’s The Founding of the Republic and the latest TV adaptation of Dream of the Red Mansions. All of these were reconstructed on Lot Six from several now-defunct studios, along with a costume gallery and a bizarre fake forest in Lot Seven – not used for any actual filming, but supposedly there to showcase the production company’s sound-effect capacities (cue generic frog noises and running water).

Luckily the production base also has an impressive back lot, first constructed for Forever Enthralled, Chen Kaige’s sumptuous 2008 biopic of Peking opera singer Mei Lanfang. Here we found a sight that was at once both recognisable and unfamiliar: Qianmen shopping street – minus the Starbucks, tourists and tacky storefronts. Instead, the signs were written in traditional characters and the dirt street was empty except for a period tram and carts – which were, somewhat disconcertingly, connected to real horses.

Turning off into a side street, we discovered that these animals, thankfully, hadn’t just been left there; they belonged to a crew filming Huoxian San Xiongdi, yet another series set during the Japanese occupation, which stars Liu Ye (Balzac and the Little Chinese Seamstress; The Founding of a Party) as one of the titular xiong di (‘brothers’). We passed extras in Kuomintang uniforms, stalls laden with vegetables and silks, a period cinema and even a Japanese inn complete with tatami rooms and a facsimile of The Great Wave hanging on the wall.

It was easy to imagine we’d been transported back in time – that is, until we looked behind the facades. Stepping through the revolving door of a hotel on Shanghai Street, we found, instead of a lobby, a blank wall. A stone church, on closer inspection foakleys, turned out to be made from wood and Styrofoam, with exposed scaffolding round the back. Returning to the ‘Beijing’ side, we encountered a man in jeans and duffel coat handing out rifles from the back of a white van to soldiers in period dress.

The whole day had been a surreal experience – not least our close encounter with Keanu – but one certainly worth making the journey out to Huairou for.

State Production Base of China Film Group

How to get there: Take bus 866 from Dongzhimen bus station to Zhong Ying Jidi.