The digging up of the past – and the hiding of secrets in the present – are the themes of Valeska Grisebach’s complex, subtle, opaque new drama which seems to withhold some of its narrative meaning from the audience, moment-by-moment. It is set, like her previous film Western, in Bulgaria’s remote and beautiful mountainous country, where memories of the Balkan wars (and the communist era before that) are still fresh and where there is money to be made and resources to be exploited for those who are ruthless enough.

As with Western, Grisebach uses nonprofessionals for many very likable supper-and-drinking-and-reminiscing scenes with people gathered round tables shooting the breeze, scenes that don’t need a particular reason to exist, other than their easy, garrulous energy. And as before, Grisebach shows an interesting reluctance to conform to conventional narrative templates – though while this film actually does conform to Chekhov’s ancient rule about what happens to the gun produced in act one (well, act two in this case), the denouement isn’t the usual arthouse flourish of violence. I felt however that in the course of this film, Grisebach was feeling and improvising her way through all this ambient detail towards a meaning that she (and we) didn’t really reach.

Veska (Yana Radeva) is a woman running an archaeological dig in Matochina in south-east Bulgaria. Out of the blue, she runs into an old friend (or maybe more than that); this is Saïd (Syuleyman Alilov Letifov), a man on the fringes of some dodgy business deals who has showed up in the locality (which he hasn’t visited for decades) to buy stolen diesel fuel from an up-and-coming local villain nicknamed Raven. Saïd turns down an offer to help with this man’s chilling, lucrative people-trafficking network: a growth business for organised crime in this part of central Europe.

In fact, Saïd’s appearance here is resented by many locals, who remember his theft of a cigarette shipment – in which Veska had been involved, before she reinvented herself as an archaeologist – and Saïd’s onetime involvement with an even bigger gang boss called Illya who wants to build a road on Veska’s archaeological site. Saïd’s old 90s Passat car is stolen, perhaps for trafficking purposes, perhaps to warn him off, and actually Saïd disappears himself – though not permanently, and not with any clear explanation. In his absence, Veska takes it on herself to sell the contraband diesel that Saïd has bought, though the mechanics of doing this mystifyingly happen off screen. Veska is tough, for all her genial, grandmotherly style, and she intends to confront Illya about the violence and abuse of his trafficking business which she has known about for decades and which threatens to involve a teenage girl working on Veska’s dig.

The interest of the film resides not really in any adventure, dreamed or real, but in all its incidental detail: the ruggedly beautiful countryside, the stately restaurants and hotels from the communist era, and the parade of people who emerge everywhere, including a platoon of Polish women working in a nearby solar-panel factory. This last is a group of people who look like the real thing, which Grisebach couldn’t perhaps resist including in her film. The Dreamed Adventure is clearly the work of a director with a fluent, distinctive film-making language, but what she is trying to tell us is elusive.