JUST before Monday night's opening show in the cells of York Castle Museum, an email arrived with Important Audience Information in block capitals.

In a nutshell, it read: "A Restless Place is a promenade production where you’ll be led around the cells at the museum dating back to the 18th Century. The floor surface in the cells is uneven, doorways low and there may be limited light at times. Please wear suitable footwear and clothing as you’ll be on your feet for quite a lot of the performance. The show includes high-volume sound and some flashing light. A Restless Place runs for approximately 50 minutes with no interval. Latecomers will not be admitted."

This still does not prepare you for the "welcome" on arrival, where a brusque security guard (Luke James) stamps some hands with a butterfly stamp, but not others. The reason why will become apparent later. There are 30 of us; we are advised to remove warm clothing before entering the clammy cells, where the suitcase-carrying story collector Anansi (Sara Sadeghi) is allotted 55 minutes to tell verbatim stories of those who have made York their home.

By now the security guard has locked the doors. He can turn heavy without warning, bursting down the corridors, setting off blaring alarms, or ordering the "butterfly" half to cram into a small cell, where the heat rises so quickly. Pilot associate director Katie Posner wants the audience to "have a feeling of oppression, disruption and being uncomfortable"; multiply it more times than you can imagine for those seeking to migrate to Western Europe in such numbers at present.

Posner and writer Juliana Mensah, from the Centre for Applied Human Rights at the University of York, have drawn together stories that highlight the myriad, restless routes of moving to York.

Mustafa Shareef's Papillon is a Syrian student, on a scholarship at the University of York, who has struggled both to maintain connection with his family and to make friends here; Mandy Newby's Sasha has been tossed between passports and identities, sometimes safe, sometimes not. Falmata Lawan's Joy, from Africa, has felt a freedom as a woman she had never experienced before.

Canadian lawyer Daniel (Matthew Evans) has a Malaysian wife, Scottish and English parentage, and a child whose first identity is York.

Wartime refugee Ana (Lou Broadbent), now 79, considers herself British, rails against the 21st century wave of economic migrants and sits for nude portraits by Edu (Lucas Smith), an Argentine painter and writer, whose father was among "The Disappeared" in his home country in the 1970s. Only now has he found York coming alive, when his subjects remove their clothes and shed their inhibitions too. Ana, most memorably, says that her body is her home, the only constant she has had.

Perceptions of York from outside can make us laugh (such as Daniel's bemusement at our love of pets), but make us uneasy too, when we hear of Papillon, a man of such intellect and original thinking, feeling so adrift. This is a moving show in every way; vital theatre for these troubled times.

A Restless Place, Pilot Theatre, York Castle Museum, until Saturday, except Wednesday. Box office: 01904 623568 or at yorktheatreroyal.co.uk. BOOKING ADVISED