Having dispensed with all that salacious “Is Jack back?” stuff, BBC One’s new period drama moves this week into the world of Victorian street gangs, complete with crooked prison guards, underground gambling and juicy back stories.

In a nod to Dickens, the villain is Misfits star Joe Gilgun’s Scouser nutbag Carmichael, who spends this episode running around beating people to death with his belt like nobody’s business. With his rotten teeth, psychopathic tendencies and band of sooty-faced urchins, Carmichael is part Fagin, part Bill Sykes and all scenery-chewing fun, proving – once again – that the real strength of this show is its cast.

After a toy maker is brutally dispatched in an alleyway, 14-year-old street kid Thomas Gower is quickly fingered and dragged up to the police station by a group of vigilantes, led by Michael Smiley’s George Lusk. Our staunch hero Inspector Reid (Matthew Macfadyen) clashes with Lusk – who will undoubtedly crop up in the coming weeks – but must reluctantly admit that the boy seems to be responsible.

Soon sentenced to death, Thomas awaits his death in silence while Reid, right-hand man Drake (Jerome Flynn) and forensics expert Jackson (Adam Rothenberg) investigate the case further, quickly uncovering that it’s all tied up with that shady Carmichael fella. The moral being never trust a Scouser, apparently.

In a development from last week’s strangely underplayed villain, Gilgun’s gurning, fidgety performance takes centre stage, nicely complementing Macfadyen’s stoic turn as Reid, whose past is delved into a little more this week when we discover his young daughter went missing some time ago.

Elsewhere, sidekick Drake also gets a bit of colour when he shows off a seriously regrettable arm tattoo, supposedly given to him by an Egyptian holy man as some sort of spiritual balm for past sins.

By far the most compelling character here, though, is Rothenberg’s Homer Jackson. This week, Jackson’s got his own troubles, having gambled away a rather important and potentially incriminating ring to none other than – you guessed it – big baddie Carmichael.

We get a little more on his relationship with feisty madam Susan (MyAnna Buring) and though there are frustrating leading lines being dropped all over the place (“You forget who we are, what we have done”), there’s certainly enough going on to keep you watching.

Despite borrowing heavily from both the recent big and small screen Sherlock Holmes adaptations, and laden with the familiar sins – clichéd dialogue, heavy-handed exposition, Cockney prozzies with hearts o’ gold – Ripper Street continues to be tremendously watchable and occasionally even a little surprising. You also get the feeling that, much like those dodgy back-alley gamblers, this series has a still got a few cards up its sleeve.

Aired at 9pm on Sunday 6 January 2013 on BBC One.

> Order Ripper Street on DVD on Amazon.

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