ITV’s has refused to bow to pressure to move its teatime drama Jekyll and Hyde to a later slot after the watershed, despite more than 500 complaints about violent scenes in the broadcast on Sunday evening.

The drama, shown at 6:30pm, featured scenes of a man being bludgeoned to death within the first minute, and went on to include further grisly deaths and potentially disturbing imagery.

TV said it had received 280 complaints, while 263 people contacted broadcasting regulator Ofcom to express their concern about the show.

ITV confirmed it would go ahead with a planned shift to a 7PM slot for Jekyll and Hyde starting 1 November, and said are no plans to move the remainder of its 10-episode run to after 9pm.

An ITV spokesperson highlighted a warning broadcast before the start of show “advising the parents of younger children they may find some scenes scary”.

The show is currently available on ITV’s video on-demand service but comes with a warning saying the content would usually be broadcast after the watershed or “contains content or themes that may be unsuitable for some viewers”.

Based on the Robert Louis Stevenson novel, Jekyll and Hyde follows the nephew of the original Dr Jekyll in 1930s London as he encounters monsters and a shadowy government organisation that fights them led by Richard E Grant.

Tom Bateman, who plays Dr Jekyll, is at one point seen putting his foot against a child’s throat, and a number of other characters, including a half-man, half-dog creature, meet grisly ends, such as being set on fire.

Ofcom is expected to assess whether to investigate Jekyll and Hyde under rules governing the protection of under-18s and clauses about programming that causes harm and offence. The regulator cannot order a broadcaster to change the time of broadcast, but takes the watershed seriously in assessing whether to impose sanctions.

Last year, US-owned network Discovery was fined £100,000 for daytime broadcasts of a programme about serial killers called Deadly Women during the school holidays. However, that is considered an extreme case and ITV is unlikely to face similarly punitive repercussions.

An Ofcom spokesperson said: “We will assess these complaints before deciding whether to investigate or not.”

The £14m series was created by ITV’s in-house production arm and written by Charlie Higson, the man who helped create The Fast Show, the Young James Bond novels and a slew of zombie films.

The show is designed to appeal to the same family audiences the BBC has previously won over with fantasy shows such as Doctor Who, Merlin and Atlantis and ITV is also hoping it could prove a hit overseas to offset the large budget.

Its premiere drew an average audience of 3.4 million and a 15.6% share of TV viewing between 6.30pm and 7.30pm, some way off the audiences the BBC has been able to attract for its own teatime viewing.
Atlantis, which was cancelled after just two seasons, debuted in 2013 with nearly 6 million viewers and Doctor Who continues to be a ratings hit. The first episode of the latest series starring Peter Capaldi began last month with the smallest audience of any series opener since it was brought back a decade ago, but still managed to attract 5 million viewers to its 7:40 Saturday night slot on BBC1.

The BBC has also attracted criticism for overstepping the mark with shows aimed at families. More than 100 people complained about a Doctor Who episode broadcast last year which dealt with theories about the afterlife and references to how the bodies of the dead could feel the pain of being cremated.

However, the repeated episodes of violence in Jekyll and Hyde appears to have provoked an even stronger response.

Higson told the Guardian before the show’s broadcast that children would be happy with the dark tone.

“Kids will be happy with it, they love all that stuff,” he said. “You never want to dumb it down. There’s enough fantasy element to it. We don’t do squirting blood, torn-off limbs. [But] kids know what they can deal with. I’ve always maintained it is good to scare children.”

The furore may raise concerns over the show ITV has lined up for a similar time slot in January once Jekyll and Hyde ends its run. Beowulf: Return to the Shieldlands is based on the grisly Old Norse poem about the battle between the eponymous hero and man-eating monster Grendel.