He knows you're blind.
2 seconds sound clip from Darkwing Duck - Duck Blind (S1E8).
You can hear this line at 00:12:58.177 in the DVD version of the TV Series.
Quote context
[...]
- Rise and shine, St. Canard. This is your wake-up call.
- And hello to you, Darkwing Dork.
- Three blind mice, three blind mice.
- Now, for those of you who like clues...
- If you wanna defeat me, meet me at First Light.
- We now return you to your regularly scheduled program.
[...]