Orlando Bloom says his best friend went missing ... and he's pleading with the public to help him find his wayward pooch.
The 'Pirates of The Caribbean' star says his super-cute furry friend, Mighty, is missing in Montecito, CA, a coastal town just outside Santa Barbara, and he's offering a reward for the dog's safe return.
Orlando says Mighty has a microchip and the little dog's collar has a phone number to call ... and he's asking anyone who finds the lost pup to take him to a local veterinarian, animal shelter or police station so he can be traced back home.
It's pretty sad ... Orlando's asking folks to only send "real info" that could lead to the dog's rescue because his heart is already broken and he doesn't want insult added to his injury.
Here's hoping Mighty finds his way home.