There's something about a vanishing supply of magic dust, which probably accounts for the glumness of Peter Fonda, who plays a grandfather longing for his happy childhood . ( Fonda, whose character is too depressed to be intimidated by Baldwin's ferocity, seems to be starring in " Ulee's Train . " ) Mara Wilson, the young actress who played one of the children in " Mrs . Doubtfire " and starred in " Matilda, " portrays his granddaughter.
