Frieder Schlaich based his 2000 German film on the 1989 confrontation between Stuttgart police and Frederic Otomo, a Cameroonian immigrant who slugged a ticket taker who'd tried to throw him off a tram. Though he's been in Germany for eight years, Otomo has never been permitted to work; carrying a bag of his native soil everywhere, he dreams of being a helicopter pilot and endures the crudest racism (one cop characterizes any humanity toward him as "animal-rights activism"). Schlaich fictionalizes the few hours Otomo spent on the run, having him meet a young girl and her sympathetic grandmother, and Isaach de Bankole gives a compelling performance as the persecuted outsider, speaking little but exuding a gentle grace. The film's imagery is almost always taut and geometrical, emphasizing intrusive diagonal lines and frequent shifts of perspective. The fragmented compositions isolate the characters, trapping them in walled-off worlds--which makes the brief kiss between Otomo and the grandmother all the more touching. 85 min. A 35-millimeter print will be shown. Gene Siskel Film Center, Friday, August 3, 6:30, and Saturday, August 4, 6:00.