When a pernickety hitman assassinates the wrong target he is wounded and has only two hours to eliminate his betrayer before the Mob kills him.

Something about pernickety makes me think this is a comedy (but "Grim Game" tells me it's not). Fastidious?

I reread it. I get it now. You need a comma between the words "target" and "he."

The clause, "he is wounded," seems like it just fell in there?