L.A. movie openings, May 18

A detective and his four-legged partner go undercover to crack a case at a high-stakes pageant for pooches. With Will Arnett, Chris “Ludacris” Bridges, Natasha Lyonne, Jordin Sparks, Gabriel Iglesias, Shaquille O’Neal, Alan Cumming and Stanley Tucci. Written by Max Botkin, Marc Hyman. Directed by Raja Gosnell. (1:32) PG.