Lyra Heartstrings is a cantankerous secret agent, to put things mildly. At least she can do her job well. Having her as a roommate is another story entirely.
You never know who has an interest in your career, or when that career might have the most extreme shift possible. Lyra Heartstrings is about to find out that there are far worse things to happen during a performance than playing a few wrong notes.
Amethyst Star has been trained to handle threats to Equestria. She was not trained for children. Her first night watching one makes her rethink what should have been covered at the academy.
The PPP is a secret oganization tasked with keeping Equestria safe. No pony knows who they are; their agents blend into the background just like any other pony. With their expertise, keeping the unicorn Twilight Sparkle safe should be no problem.
The PPP has a long history of keeping Equestria safe. A long and often untold history. When a sect attempts to resurrect an ancient spirit, old, harsh truths come to light and threaten the foundation of this secret agency.