Normal sudoku rules apply. Clues outside the grid show the sum of digits sandwiched between the 1 and 9 in that row/column. Some flies have got into some of these sandwiches. Each cell with a fly (Ѫ) is either 'sandwich filling' (included in the sandwich sum) or 'sandwich crust' (1 or 9) for one of the clued sandwiches. The grid also contains a couple of 'palindromic worms. The digits along the worms read the same starting at either end. Some of the clues have been replaced with letters. Each letter represents a different digit from 1-9.