A power cut across the capital forced MSC Cruises to close its offices in Holborn yesterday.
A spokeswoman said the operator sent home members of staff from the reservations, marketing and accounts departments as well as senior management after they arrived at work only to find both their computers and phones were inoperable.
She added: “Most of them have lap tops which they took home and plugged in so they were still dealing with emails and were making phone calls if any emergencies arose.”
Electricity providers EDF Energy Networks said the near 24-hour power cut was caused by a Thames Water main bursting, flooding a substation with 15ft of water.
By lunchtime yesterday 85% of all customers had their power restored with final maintenance completed by 10pm last night.