You must act quickly, but there is a chance. First, don't plug the battery in or try powering it on. Second, get some alcohol as specified in the guide below. Then, disassemble and clean your drone with the alcohol, using the below guides. The "Repairing iPhone liquid damage" guide demonstrates water damage cleaning well. The sooner you do this the better chance of survival. Remember to clean all PCB thoroughly.
Hope this helps.
[guide|5825]
[[Electronics Water Damage]]
[guide|72122]