It's a Mystery, Charlie Brown
- Ane: 1974
- Peyi: United States of America
- Stil: Animation, Comedy
- Studio: Lee Mendelson Film Productions, Bill Melendez Productions
- Mo kle: detective, dog, beagle
- Direktè: Phil Roman
- Distribisyon: Todd Barbee, Melanie Kohn, Stephen Shea, Donna Le Tourneau, Jimmy Ahrens, Lynn Mortensen