Coronation Street is to switch to 9pm for a week as the show goes to six episodes for a nail-biting and explosive siege.

Soap bosses are giving fans an extra fix with a one-off additional episode on ITV1 as the tension comes to a head between Monday, May 31 and Friday, June 4.

ITV chiefs claimed the high-drama – which will be screened the same week as Britain’s Got Talent’s live heats – are the Street’s ‘most expensive episodes ever filmed’.

Viewers will see convicted killer Tony Gordon (Gray O’Brien) escape jail and exact revenge on those he believes responsible for his downfall.

With the help of new henchman Robbie Sloan (James Fleet), Tony targets his ex-wife Carla (Alison King), lover Maria (Samia Smith), nemesis Roy Cropper (David Neilson) and Roy’s wife Hayley (Julie Hesmondhalgh) and holds them hostage in knicker factory Underworld.

The first show of the week will be screened on Monday at 7pm, followed by a 9pm show that night and for the next four evenings.

Coronation Street bosses promised the episodes would still be suitable for family viewing despite their post-watershed time slot. They remained tight-lipped about the exact cost of the episodes.

The scheduling change coincides with the Britain’s Got Talent live shows, which will be broadcast each night from 7.30pm to 9pm, with a nightly results show at 9.30pm, ahead of the final on Saturday, June 5.

Additionally, both Coronation Street and Britain’s Got Talent will be broadcast on ITV1 HD as the soap is joining the channel from May 31.

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