Ah well, perhaps it was too good to last. After three excellent episodes and one sensational one, Being Human has fumbled the ball slightly by falling back on one of the oldest plots in comedy: the love spell.

While it’s a welcome idea to expand the world of Being Human by introducing a succubus, the trouble is: for this sort of plot to work, characters are obliged to behave in the most stereotypical ways. Thus, after four weeks of building up the characterisation of the new team, this week, Tom and Hal revert to more simple-minded selves – Tom a doe-eyed lapdog in awe of the legal profession, and Hal secretly harbouring some serious love for the bride of Dracula.

The woman who is able to bring the animal out of people who have tried, all series, to resist the call of the wild is Headmistress, Yvonne Bradshaw, and she it is who, despite being the newest character, is the most familiar of all.

Like the love child of Alastair Sim and Joyce Grenfell, she threatens Adam with the naughty step, is shocked but flattered by Adam’s smutty come-ons, and considers herself a woman of the world for knowing a member of Amnesty International. For her, grubby talk and sloppy alliteration are the twin crimes of the gutter press.

Writer Tom Grieves – on such fine form last week – works hard to imbue Yvonne with pathos, particularly in the standout scene when she presents herself to the press as a ‘monster’, but it’s not enough. This is Being Human deliberately playing as farce, and, as such, it’s dependent on the next person to succumb ludicrously to Yvonne’s charms. When Hal ‘murders’ Tom, it should be horrific and devastating, but in an episode where the comedy is this broad, the certain knowledge that this can only be a dream sequence undermines the scene’s impact.

The addition of Series 3 guest star, Craig Roberts, to the mix goes some way to souring the farce. Permanently horny and with the adenoidal drone of the perpetual teenager, despite being 46, Roberts perfects a sullen-eyed stare that is at once adolescent and vampiric.

In his insistence that he is a superior ‘swordsman’, he is gifted some of the episode’s best lines. But it’s when he drops the sneer that he most lives up to the programme’s title and mission statement. In an episode that is in many ways disappointing, Adam’s line about love rings as beautifully true: ‘Just because we’re a bit rubbish and we’re cursed because of what we are doesn’t mean we can’t be happy.’

However, ultimately, the interest in the episode does not come from the main plot but from the ongoing story arc about Cutler’s exposure of the werewolf community. Andrew Gower as Cutler has given one of the standout performances this series, and the scenes where he becomes cornered by journalist Pete are as compelling as any in the episode.

As the episode ends, with the prospect of more exposure to come, there is the feeling of a show beginning to work its way up towards the end game.

Aired at 9pm on Sunday 4th March 2012 on BBC Three.

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