Snoopy the beagle receives a letter from a little girl and sets out with his sidekick, Woodstock the bird, to go visit her at the hospital... leaving Charlie Brown distraught over his dog's sudden disappearance. It's later revealed that the girl, Lila, was Snoopy's former owner, and now he's faced with the decision to stay with her or return to Charlie Brown. Easily the most popular of the non-holiday themed Peanuts films, this one premiered theatrically and has gotten tons of exposure over the years on television. It's had multiple video releases and is now available on DVD.