Celebrity Big Brother's launch gave Five one of its biggest ever audiences with an average of 5.1 million tuning in last night.
The show and its spin-off programme were the most-watched programmes on TV last night between 9pm and 11.30pm, overnight data reveals.
However the launch audience figures were slightly down on those for the opening of the final Celebrity Big Brother on Channel 4 last year.
Last night's debut on Five peaked at six million just before 10pm. The celebrity version of the show debuted with an average 5.6 million in 2010, peaking at 6.2 million.
However the programme seems to have weathered the predicted plummet in viewing figures which had been forecast for its move to the new channel.
Other popular shows which have moved to the station such as Home And Away and Neighbours saw an immediate downturn.
Contestants in the new run of the series include Kerry Katona, Sally Bercow and the Jedward twins.
Five said the launch show was in the top four biggest audiences since the station launched in 1997.
And excluding sport, yesterday's launch was the most watched British programme since the station went on air. Its largest audience to date was the Euro 2000 qualifier - England v Poland - with 5.6 million viewers.
"Consolidated" figures which include time-shifted viewing are expected to increase last night's figures when they are compiled in a few days.