It's human nature to assume the worst, the theory being if something is too good to be true it probably is. Plus the higher expectations are for something the more likely it is that they're not going to be reached.

Pity then the cast and crew behind Being Human, one of the more hotly anticipated new shows of 2009. When last year's one-off episode shown on BBC Three inspired mass lobbying of the Beeb for more, little did the people behind it realise that with this popularity came a backlash.

At least not until - when the show was finally commissioned - they announced two thirds of the main cast had been changed because they were looking for a younger audience with the full series. Cue lots of terrified fans worrying they were going to be watching Hollyoaks with fangs and that everything they loved about the pilot was going to be lost.

Well we've seen episode one. And we can tell you now, you have nothing to fear.

Set about a week after the events of the pilot, episode one assumes you know nothing about what's come before. This means all three origin stories are explained, the basic premise of the show is established and Russell Tovey is naked within the first three minutes. And with everyone caught up and on the same page (and George is back in his clothes) the credits roll and the series begins.

There's a lot packed into this first episode. George (Tovey), Mitchell (Aidan Turner) and Annie (Lenora Crichlow) are getting used to domestic life together and, bar the odd row about Annie's propensity to make endless cups of tea she can't drink, everything seems to be going well in Bristol's most unusual house share. But when werewolf George's time of the month throws up even more problems than usual, the house gets a visit from their landlord (and ghost Annie's ex - all kinds of awkward), and Mitchell's attempts to stay on the wagon are being undermined by vampire leader Herrick it isn't long before the fragile normality they've been able to establish looks in danger of shattering, leaving those close to them in mortal danger.

Those worrying that the camaraderie of the three flatmates couldn't be as warm and believable as before can rest assured, our triumvirate is on good form and remain the focus of the humour and heart of the show. Tovey gets most of the best lines in the first episode, but Turner and Crichlow are both given enough to do - including some genuinely moving moments - to showcase their talents and make the roles their own. This is a slightly different dynamic to what we've seen before, but on the basis of this episode I'd say it was definitely as good as the pilot. Give me another couple of episodes to base my opinion on and I might even go further and say it's better.

The vampire subplot, while still of significance, has been ratcheted down the camp scale with less Anne Rice-inspired crushed velvet and lurking in dark corners. Instead the vampires - led by Herrick (now played by Jason Watkins) - are among us, and look perfectly normal and innocuous and all the more chilling for it.

The story runs at a rollicking speed, with sharp editing and a cracking soundtrack (Supergrass, The Arctic Monkeys and Johnny Cash all in episode one, we definitely need a soundtrack) ensuring that the jam packed hour flies past. If it keeps to this quality throughout the run then Sunday nights have just become infinitely better.

The episode - the first of a six episode run - was unveiled at the British Film Institute in London to a sellout crowd and assorted media luminaries last night (Friday). It was followed by a Q&A session with Russell Tovey (George), writer Toby Whithouse, producer Matt Bouch, Julie Gardner (head of drama at BBC Wales) and Rob Pursey (exec producer for Touchpaper). You can read more about that next week on www.sfx.co.uk.

Being Human will air on BBC Three on Sunday nights at 9pm from Sunday 25 January 2009.

This article contributed by writer Narin Bahar. For more about Being Human, visit the official BBC blog.