Large swathes of Perthshire and part of Fife were hit by a power cut in the early hours of Friday morning.
Hundreds of houses in Glenfarg, Abernethy and Aberargie were affected, as well as the Fife village of Strathmiglo.
The outage hit at around 3.30am and was caused by a fault on Abernethy’s Main Street.
A spokesman for Scottish Hydro Electric power distribution said engineers took more than three hours to restore power.
He said: “There were 668 customers off supply. The power went out at 3.32am.
“We restored power in phases, with the last person being reconnected at 7.02am.
“There was a fault in our overhead network, which power engineers fixed.
“We apologise for any inconvenience and disruption caused to our customers.”