Sunday night's launch episode of I'm a Celebrity... Get Me Out of Here! on ITV has become the fifth-biggest programme on TV this year.
The reality show, which is now in its 20th series, attracted a peak of 12 million viewers last night at 9.41pm, according to overnight figures provided by ITV.
Airing between 9pm and 10.30pm, the average audience that tuned in was up 10% year on year to 10.9 million – a 51.9% share of the total number of people watching TV at the same time.
It was the second-biggest launch for the show since 2013 and the fifth-biggest launch episode for the show ever, ITV said. The 2018 launch show attracted 14.2 million people, according to consolidated figures.
ITV has had to change the show's filming location from Australia to a castle in Wales because of the Covid-19 outbreak. It is the first time that the programme has been filmed in the UK.
Celebrities including Olympian Mo Farah, presenter Vernon Kay and actress Beverley Callard are among those taking part. The show continues to be hosted by Ant McPartlin and Declan Donnelly.
ITV said that last night's show also pulled in the highest-ever share of 16- to 34-year-olds at 77%. Overnight figures recorded an average of 2.7 million, with a peak of three million viewers.
It is the fifth most-viewed show on TV so far this year, behind the Queen's address in April and the Prime Minister's Covid-19 statements, ITV explained.
It added that outside of news programmes, I'm a Celebrity... is now the biggest overnight audience on TV since the Gavin & Stacey Christmas Special on BBC One last year.
The high audience numbers will be a welcome relief for the broadcaster, which has recorded declining viewers for The Voice and Britain's Got Talent. It also had to cancel Love Island this year.
Average viewer numbers for the final of ITV's The Voice on Saturday night (14 November) fell 29% to 3.3 million, or a 19% share. It peaked at 3.6 million. Production for the series was interrupted because of the coronavirus lockdown earlier in the year.