Yeah it runs offline mate just go to https://github.com/sc0tfree/mentalist/releases/tag/v1.0 and download Mentalist-v1.0-OSX.zip
Also running something offline doesn't always make it secure, this is a protip. If you want to be extra safe, Run this on a live usb or an old laptop with the network device removed &/or disabled from the bios.
Malware can aggregate data offline for posting it out later on, also crash reports, memory persistence happen too.
I didn't really realize that; thank you! I did plan on moving everything out, if ever found and changing the passphrase etc. before formatting the laptops and enabling wi-fi. I like your suggestions though.
Is there a Windows version of Mentalist?
In my opinion, you should use Debian or at least Ubuntu! A Linux distro will be way more secured than Windows. Maybe, it is just my pro-linux propaganda which is talking right now
but it is never too late to start using Linux, and you won't regret it for sure