M A    C         
        R   .       
 U K    . . L      R
          K    T    
          A    . M  
 M   .  .      A   I
   L I    .    .    
 .        T U  K    
        I   .      L

Code-Doku Joke

What has one horn and gives milk?

Place each of the letters of TRIAL MUCK exactly once in each row, column and 3×3 box. In addition to the letters, each row, column and 3×3 box will also contain one empty square. When you have completed the puzzle, the shaded squares will form the punch line of the joke read left to right, then top to bottom.

Difficulty: Challenging

Please send responses to my email address is mathrec at this domain