Fantasy series Game of Thrones marked its return to UK TV screens with its highest viewing figures to date.

The first episode of the grisly blockbuster’s sixth series, starring Huddersfield actress Lena Headey, has so far been watched by an estimated 2.2 million people on Sky Atlantic.

This is the highest overnight audience the channel has enjoyed since its launch in the UK in 2011.

Around 60,000 fans watched the episode’s first broadcast at 2am on Monday – the same time as its premiere in the US.

A further 1.3 million Sky subscribers caught up with the show at some point during the following day, with another 0.8 million watching the repeat on Monday night.

The total audience of 2.2 million is the largest for any episode of Game of Thrones in the UK.

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It is likely to increase when catch-up viewers are included.

The Monday night repeat managed to beat one of the main terrestrial channels, with Sky Atlantic’s 0.8 million pipping the 0.7 million who tuned in for BBC2’s Horizon: How to Find Love Online.