Thinking about moving from Network Engineer role to Security. What to expect?

As my title said, I have a potential opportunity to move from my current role as a network engineer into a security role at a new company. This change would as come with a considerable pay bump and better benefits.

Currently I am the only network guy in a company of 4000 employees, so I get a lot of hands on stuff and plenty to do. My education included a healthy blend of network and security, and I always thought a lot of the security principles were interesting.

What could I expect moving to a security role instead? Would I potentially find it boring? What sort of things should I ask at an interview?