I’ve been trying to get an impression of the underground music scene in Tehran.
While this sub-culture naturally attracts journalists and film-makers, this is not merely exotic decoration for our jaded palates, but a manifestation of urgent issues confronting young people in Iran—in particular, the options for women to express themselves within tight constraints (cf. Persepolis). This alternative scene makes an outlet for frustration (cf. GDR, China)—and often a route to emigration.
Your go-to authority on the variety of musicking of Iran is Laudan Nooshin. Further to her survey in The Rough Guide to world music (2009), she has published significantly on the popular music scene—  a scene, of course, that continues to evolve.
A few vignettes that I’ve spotted via the media: 
On the underground metal scene, here’s the incisive short feature film Forbidden to see us scream in Tehran (Farbod Ardebili, 2020) (see e.g. here, here, and here):
Earlier films include Not an illusion (Torang Abedian, 2009) and No-one knows about Persian cats (Bahman Ghobadi, 2009):
Here’s an excerpt from No land’s song (Ayat Najafi, 2014; wiki, here, and here):
For Sanam Pasha (who chose to remain in Iran) and her all-female rock band, here’s an interview from 2018:
A related scene is rap and hip-hop (e.g. here and here)—here’s Salome MC (wiki, and here):
And there’s a sub-culture of electronica.
Of course all this a minority culture (even in Tehran, let alone Iran), but the endeavours such musicians face are just some of the myriad challenges faced by women and men there daily.
On the broader soundscape, the Sonic Tehran project has much interesting material.
For more on Iran, see under my roundup of posts on West/Central Asia. See also Punk: a roundup.
- “Subversion and countersubversion: power, control, and meaning in the new Iranian pop music”, in Annie J. Randall (ed.), Music, power, and politics (2004)
- “Underground, overground: rock music and youth discourses in Iran” (2005)
- “The language of rock: Iranian youth, popular music, and national identity”, in Mehdi Semati (ed.), Media, culture and society in Iran: living with globalization and the Islamic State (2007)
- “ ‘Tomorrow is ours’: re-imagining nation, performing youth in the new Iranian pop music”, in Laudan Nooshin ed., Music and the play of power in the Middle East, North Africa and Central Asia (2009)
- “Whose liberation? Iranian popular music and the fetishization of resistance” (2017).
 Some general introductions include