My house has a multi-branch circuit on it. This circuit supplies power
to a few bedrooms and a bathroom. The two breakers that supply power
to the circuit are 20amp each.

At 7pm tonight I turned on a few things in one bedroom. This bedroom
has two duplex outlets. Everything I turned on worked. At 7:15pm the
entire room had no power. Neither the outlet I was using at 7pm had
power nor did the room's other outlet.

I checked the two breakers that supply the circuit; neither had
tripped. There are no gfi outlets involved. In the panel I checked
the hot and neutral wires for the circuit; all are tightly attached.
All of the other bedrooms in the house had power at 7:15pm with no
obvious issues.

What on earth could cause this? How would I troubleshoot this problem?

Thanks,

mh