Kate DiCamillo's 2003 children's novel about a big-eared mouse with an inspiring case of shining-knight envy is one of the finest expositions of loss, grief, reactive vengeance, and forgiveness for kids. I was looking forward to seeing what Sylvain Chomet, who made the fabulously weird The Triplets of Belleville, would bring to this great yarn, which trusts small children enough to understand the concept of mixed motives and empathize with hurt rats who hurt in return. Alas, for murky reasons, Chomet was bounced from the project shortly after it was green-lit; only his production designer, Evgeni Tomov, remained. So The Tale of Despereaux looks good, in a washed-out, Flemish-masters sort of way. Otherwise, screenwriter Gary Ross, who made the cornball Seabiscuit, and directors Sam Fell and Rob Stevenhagen have seen fit to turn this delightful tale into, of all things, an intermittently vicious CGI action movie in which the mouse (voiced by Matthew Broderick) who refuses to cower gets dumped down a well into a dungeon and shoved into a terrifying gladiatorial battle with a gruesomely drawn cat before he can even start saving the world from darkness and gloom. Clumsily wedged in like a TV commercial between deafening stunts, the emotional storytelling sinks without trace, leaving you with only one flawed character to cling to — a morally challenged Cabbage Patch–like servant (wittily voiced by Tracey Ullman) who learns that every girl is somebody's princess.