What's the meaning of "shide" in this context?

There is a sentence in a book i am reading currently:

‘Doh. I wanna finish this head-choppin’ stuff and leave this shide
down.’

The character is telling his mafia boss to go into a place and behead the man they want to kill, but his boss tells him to wait. Afterwards he says this sentence. He is using a slang language as you can see and i couldn’t understand “leave this shide down” part in the sentence.

He also says “Bloody shide down” before he swings his sword to kill the man. I would be delighted if you can help me with this word. Is this a slang or deformed word in English? Because its lexical meanings have nothing to do with the context.

Thanks in advance.