Her given name is Lilith and, having been raised by lions in Borneo, she has been captured by 19th-century colonisers as a scientific specimen and transformed, Pygmalion-like, into the very image of a civilised woman. But an image is all it is and, in what is quite the silliest treatment of the theme of identity politics on a Fringe in which the subject is everywhere, she has not yet lost her bite. In Lilith: The Jungle Girl, a funny piece of slapstick playfulness by Melbourne’s Sisters Grimm, keeping narrowly on the right side of flippancy, we hear an echo of how immigrants are treated in the 21st century. Behind the metatheatrical gags, the fruity accents and the pastiche melodrama is the serious suggestion that today’s nationality tests and exclusionary immigration policies are a form of savage-taming. These issues of subjection and the relationship between old and new cultures are central, too, to Selina Thompson’s Salt, a powerful personal narrative about how a descendent of slaves comes to terms with a society still riven with racism. In an attempt to reclaim her identity, Thompson took a real-life trip in her ancestors’ footsteps on the triangular transatlantic trading system connecting the UK to Ghana and Jamaica, seeing first-hand the legacy of colonialism. “Europe pushes against me,” she says. “I push back.” The force of political insight, the spark of her passages of spoken-word poetry and the easy-going rapport she establishes with the audience give Salt its voice of urgency. It’s an urgency born of lived experience, something that is just as keenly felt in Nassim, a superbly crafted show by Iranian playwright Nassim Soleimanpour about the importance of cross-border friendship and the pain of enforced estrangement. Now living in Germany, Soleimanpour longs to write in his native Farsi but, since being permitted to travel for the first time in 2013, has been resigned to playing to audiences abroad. “I can’t translate myself,” he writes. “I’ve become a foreigner in my own mother tongue.” The sense of dislocation is embodied in Omar Elerian’s production for the Bush Theatre: with every performance comes a new actor (an excellent Chris Thorpe when I saw it) who discovers the script as we do, enjoying its jokes, stumbling over its challenges, feeling their way into an alien tongue – artfully concealing the playwright’s greater purpose to move us with the pain and sadness of his refugee status. Given the choice, Soleimanpour would rather be writing in Tehran than Berlin, just as Javaad Alipoor would rather not be telling the story of radicalised Muslims in The Believers Are But Brothers. Today’s political climate means he feels he can’t do otherwise. In a series of digital exchanges with the audience via WhatsApp, Alipoor tells us how many Muslims there are in the UK and proportionately how few have joined Isis. One of his themes, in this adventurous high-tech show, is the misinformation that proliferates in our supposedly connected world. If those of us in secular society don’t understand what motivates the kind of disenfranchised young man whose sorry stories Alipoor relates, it’s because we are immersed in a different network of beliefs and values. Paying a visit to The Believers Are But Brothers is an excellent way to begin crossing the divide. Lilith: The Jungle Girl, Traverse, until 27 August; Salt, Summerhall, until 26 August; Nassim, Traverse, until 27 August; The Believers Are But Brothers, Summerhall, until 26 August