English Translation
We’ll bump them off!
I had no idea what the english idiom meant but apparently in this context it means to kill somebody essentially.
On Tatoeba it’s a translation from “Let’s give it all we’ve got.”
Which, conveniently, is also what the French expression “faire la peau” means. 
I think that’s pretty much all there is to it. I guess it may be considered kind of old-fashioned.
There is also “vouloir la peau de quelqu’un” (to want somebody’s skin), which depending on context can mean:
- wanting to kill them
- wanting to hurt someone, socially or professionally (maybe you want their job), although with that meaning, “vouloir la tête de quelqu’un” (to want somebody’s head) may be more common.