A brief prologue recounts Hamas' surprise victory in the Palestinian parliamentary elections in January 2006. "Palestinian prisoners are the real leaders," declares one Hamas official, unwittingly pinpointing "Hot House's" central thesis.

A year earlier, Dotan and his camera crew had been granted access to a number of high-security Israeli prisons, visiting both men's and women's facilities. The filmmakers follow the buildup to the elections through candid, intimate interviews with the prisoners, many of whom are running for seats in the Palestinian legislature.

Pic subtly argues that Israel has unwittingly handed power to those it claims to have imprisoned: According to those interviewed, every Palestinian family has at least one member incarcerated, and the close ties among the families result in strong voter turnout, making it possible -- and even likely -- for prisoners to win office.

Dotan (who last took on the Israeli-Palestinian conflict in his 1986 feature "The Smile of the Lamb") lays out the evidence in a tone of evenhanded alarm, showing an appropriate degree of respect (shared by the Israeli guards he interviews) for his disciplined, well-organized subjects. Fascinatingly, the inmates are grouped by party, with separate cells for members of Hamas, Fatah and so on, allowing for easy communication and strict chains of command.

Individually, the inmates tend to be well-read and committed to furthering their educations, viewing their prisons as institutions of learning -- markets for the free exchange of radical ideas.

"We are human beings. We treat all human beings as brothers," declares a prisoner at one point, and Dotan indeed grants his subjects their humanity, observing quietly as they go about their daily business of praying, writing letters and negotiating visiting hours with their children. Helmer also gives voice to their repeated protestations against the word "terrorist" (they prefer to think of themselves as freedom fighters).

At the same time, "Hot House" doesn't flinch from relating the atrocities aided or committed by its subjects, many of whom are serving life sentences. With the exception of a man who claims to have been arrested for no reason other than his political activity, all involved are quite forthcoming about the deeds that have landed them where they are. 

In perhaps the docu's most chilling moment, Hamas prisoner's rep Ahlam Tamimi recounts two bombing operations she executed in Jerusalem, in a tone of defiant indifference to the children who perished.

Ron Klein's music contributes a crucial element of low-key dread, focusing rather than overpowering the viewer's attention. Other tech credits are solid.

Camera (color, DV), Philippe Bellaiche, Shai Goldman, Abu Sada; editor, Ayala Bengad; music, Ron Klein; sound, Alla Khuory, Tully Chen, Ben Zion Sushon, Avner Dir, Idan Shamash, Muhamad Naji, Rami Yatzkan; sound designer, Aviv Aldema; line producer, Yariv M. Mozer; second unit director, Jonathan Aroch. Reviewed at Sundance Film Festival (competing), Jan. 24, 2007. (Also in Jerusalem Film Festival.) Running time: 90 MIN.