First Day - Die Mission (First-Reihe, Band 2)

I think if I had started the series with the story, I would have had a slightly different view on the rest of the series. Or maybe I'm just saying this because I already know the whole series and picked up on some hints. We'll never know so I can't tell you to start with this or have it be the cherry on top. But this was short and fun and I absolutely recommend it if you like stories about shifters.