Royal relations Filmmaker and former Iranian rebel Nahid Persson Sarvestani forges an unlikely friendship with her former queen, Farah Diba, in the new documentary "The Queen and I" (7 p.m., HBO2). At first, the Shah's widow is reluctant to participate, but watching her slowly warm to Sarvestani translates into a fascinating study of human nature.

All quiet on the front Two activists with Minnesota roots -- Jake Reitan and Haven Herrin -- are front and center in the documentary "Ask Not" (11 p.m., KTCA, Ch. 2), which explores the military's controversial and often confusing "don't ask, don't tell" policy. The film's strongest draw: interviews with current and veteran gay soldiers who led a double life during their tours of duty.

NEAL JUSTIN

Check, mate Not everything that ABBA touched turned to gold. "Chess," the 1986 collaboration between Tim Rice and ABBA members Benny Andersson and Bjorn Ulvaeus, never really got off the board (exception: the hit single "One Night in Bangkok"). Nevertheless, it's somewhat amusing to see Idina Menzel (left), Adam Pascal and Josh Groban (right) interpret songs from the flop in "Chess in Concert" (8 p.m., KTCA, Ch. 2), filmed last year in London. The production marks Groban's fourth appearance on a "Great Performances" special.