Philip Harris writes, blogs, and gives free books away at his website, Solitary Mindset. I enjoyed the three short stories available for free and his prequel novella to Serial Killer Z is definitely something different.
Bottled Lightning - Good short science fiction story - a first contact tale.
Curfew - Another short science fiction story, but this one is more military based. Ends as a horror tale.
Saviour - Not as good as two other short stories above but still intriguing. Harris is a very good story teller.
As to Serial Killer Z: Infection, the blurb says this series is Dexter meets the Walking Dead. Since I've not seen either nor do I want to, this zombie thrasher serial killer gore fest isn't for me.
Now I have to say, it's well written but it's pretty darn gruesome. I think this intro novella is still free, as a prequel to the author's new series. So if this is your thing, you might like it.