The new boss gives a "It's going to be great!" speech and you sort of breathe a sigh of relief. She doesn't have a headful of snakes and doesn't eat puppies for breakfast. This you can live with!
You begin trying to impress your new boss (or at least stay our of her way).
But then you notice this other person hanging around the boss a lot. It's not really clear who this new person is, other than she came on board at the same time. When you ask about her, you get some vague answers about her being the new boss's "liason" or "right hand" or something like that.
Oh, well, not to worry! You are out to ensure your position is safe with the new boss, and don't have time to worry about the "liason."
But here's what no one has said out loud: The "liason" is really part of the boss's entourage. Think of her as Eric, Turtle and Johnny to your boss. She's not the brightest bulb in the pack, but she's always around to make sure the boss stays happy and she always has the boss's back.
This all means that it would be a huge mistake to ignore this "right hand" of the boss. This person is around the boss to make her feel secure in her new surroundings, to give her insight into the team (in other words, pass on the gossip) and to do the boss's bidding without question or delay. She may even be the one to bring down the hammer on under-performing employees, or tackle difficult administrative jobs.
This person is powerful, and you ignore or underestimate her at your own peril.
So, when you get a new boss, set out to impress her. But also look around for the new "liason" that comes on board and seek to impress her as well. Help her out. Offer to introduce her to others. Make sure she understands the talents and skills you can use to make the boss successful.
If you prove yourself to be an ally of the liason instead of dismiss her as unimportant, you may just find that the "right hand" gives you a "helping hand" to bigger and better opportunities.