Mixed Doubles
- Episode aired Dec 30, 1979
- 23m
![Sport Billy (1979)](https://m.media-amazon.com/images/M/MV5BZWNlYTc5ZDUtMTRhMi00MDM2LTg5NmYtMmM2ZTFkY2VjNjg4XkEyXkFqcGdeQXVyMTYzNTE3NDA@._V1_QL75_UY281_CR49,0,190,281_.jpg)
Professor Plant has invented a growth serum for that turns plants into monsters and uses it to disturb a tennis match in Rio de Janeiro.Professor Plant has invented a growth serum for that turns plants into monsters and uses it to disturb a tennis match in Rio de Janeiro.Professor Plant has invented a growth serum for that turns plants into monsters and uses it to disturb a tennis match in Rio de Janeiro.