I love the Kidnap Gang, so it's a little sad to see the end of the series.
Why then, is it ending?
First, the arc has...well...arced. We meet the characters in KIDNAP.org (which is free here: https://books2read.com/u/mZ58rl We see them take down a really big bad guy in Pharma Con. ($2.99 here: https://books2read.com/u/mKEOVE) And we see Robin deal with her past in The Trouble with Dad. (Link above)
Second, I have other irons in the fire. Like a lot of authors, I love trying something new. While working with the same characters over and over can be rewarding and is less taxing on the brain, it can also result in stale plots and "jumping the shark," making things happen that are hard for the reader to believe. If you've ever stopped buying a series because things just got too crazy, you know what I mean.
So I wish Robin and the gang well, but I'm done with them. I did leave an opening for more books in the future. SPOILER ALERT: Nobody dies!
PS: The audio book takes longer, but there will be one!