The show follows Looney Tunes characters Sylvester and Tweety Bird, and their owner Granny, along with bulldog Hector (who appeared in several cartoons alongside Tweety, Sylvester and Granny but was in the series given a new design similar to that of Marc Antony), as they solved mysteries, even with Sylvester still trying to eat Tweety in the middle of solving the mysteries, but Hector acted as a bodyguard for Tweety, and would even beat Sylvester up (usually out of shot, but sometimes behind a blind). The first season was dedicated to the memory of Friz Freleng, Warner Bros. animator and the original creator of the Sylvester and Tweety pairing. Freleng had died only months before the series premiere. Also, it contains one case per episode, in contrast to the other seasons, which are all with two cases.
Other Looney Tunes characters make cameo appearances, including Daffy Duck, Yosemite Sam, Elmer Fudd, Tasmanian Devil, Pepé Le Pew, Beaky Buzzard, Babbit and Catstello, Hubie and Bertie, Foghorn Leghorn, Witch Hazel, Michigan J. Frog, Rocky and Mugsy, Marvin the Martian, Hippety Hopper, Gossamer, Count Blood Count, Cecil Turtle, Nasty Canasta, The Crusher, Pete Puma, Goofy Gophers, and latter-day Warner cartoon star Cool Cat who appears in some form in most of the episodes.
The final episode of the series never aired on Kids' WB (in which, after decades of trying, Sylvester succeeded in eating Tweety, but it turns out to be a dream), but did air on Cartoon Network in 2002.