I am trying to fix a problem in a gfi circuit running through 3 bathrooms. The problem started when some people removing wallpaper messed with a GFI outlet in some unknown way and likely broke it. After talking with a coworker about the problem I am now unsure of how to proceed. From what I can tell the circuit comes out of a 15 amp breaker and goes to the downstairs bathroom. Wire then comes from the load portion of the outlet and splits in 2 directions. One of these wires leads to a upstairs hall bathroom and into the lead portion of another GFI outlet. This outlet then has a load wire run out of it. The master bathroom also has a GFI outlet that only is connected through the lead.
For the record I have verified all three outlets run on the same circuit and, while working in the past, no longer work at all. I am now no longer even getting voltage in the hot wire for the downstairs bathroom and am considering replacing the breaker the entire circuit runs through. I also have no clue where the second line out from the downstairs GFI outlet goes and am still searching for it. Any help on how to fix this circuit would be much appreciated. I do have a high level of experience with electronics so am confident I can employ any fix someone comes up with.

Miller, get yourself a tester and start at the breaker. Confirm power from the breaker, both hot and neutral. Check and tighten the screws in the panel. Test again at the first GFI to see if the power reaches the GFI. All cables downstream can be protected by that GFI so no second one is needed. It is more l;ikley the GFI is bad rather than the breaker but you'll find out soon.

Agree with above, May have a gfi, line and load reversed, remove all, find power, that is line, connect remainder to load, go to other recpticles and repeat.