And to rub salt into the wounds he said electricity giant Western Power has offered them just £1,500 compensation for the shattering blow.
Kilworth House Theatre ended up seriously out of pocket after the dramatic power outage suddenly struck the packed-out venue one night.
The nationally-renowned North Kilworth theatre had to refund all 550 disappointed customers – who had forked out £39 a ticket to see the spectacular West End show.
Owner Richard Mackay also had to pay a small army of actors, orchestra, crew, bar staff and technicians despite the lights going out.
Richard told the Harborough Mail: “We were extremely upset to have to cancel a performance of Cats because of the failure of the electrical supply, with the incident costing us over £20,000 in lost profit as we naturally needed to refund all our patrons.
“It is adding insult to injury to be informed that the maximum compensation payable is limited to just £1,500.”
Richard vowed to protest to government power regulator Ofgem after the disastrous drama happened last August 4.
“We are taking this matter up with Ofgem but have little hope that this will be resolved,” he said.
“However, we were absolutely delighted that our production of Cats recently received a critic’s choice award as one of the Top 50 shows in 2019, which further makes it so frustrating that we lost a performance and some patrons missed the opportunity to see this brilliant show.”
A Western Power spokeswoman said: “On July 23, 2019, there was a fault on the high voltage cable that supplies Kilworth House Hotel and Theatre.
“Our engineers carried out an inspection and restored power via a generator at the earliest opportunity.
“Unfortunately, on August 4 there was a subsequent, unforeseen failure of the generator.
“Again, our engineers attended and arranged to replace the generator as soon as possible.
“We have been liaising with the claimant’s solicitors since August 2019 and are currently awaiting a response to our last letter.
“As a result, the matter remains in discussion.”