Picture the scene. A pretty young thing in a pristine white dress turns up on the doorstep of a brothel after an absence of two years, traumatised and begging for work. Later that day, the same girl is found wandering the streets of east London in a daze, her lovely white frock now covered in blood.

And thus opened the fourth episode of BBC One’s grimy Victorian crime drama, Ripper Street. At the heart of this week’s story was the aforementioned bloodstained girl, a prostitute by the name of Lucy Eames (Emma Rigby) who – as evidenced by her wide-eyed stare and bruised wrists – had suffered greatly at the hands of some dastardly man or other.

Inspector Reid (Matthew Macfadyen) soon discovered the blood splashed across Lucy belonged to both her mother and her mother’s murderer – killed at the scene by a mysterious other – and went on the hunt for answers. Up against him was fur-wearing gent Stanley Bone (Doctor Who star Paul McGann), desperate to get the slum where the murders took place demolished so he could continue work on his revolutionary subterranean railway network.

Yep, that’s right. You just witnessed the birth of the London Underground, people! Inevitably, Reid cracked the case, saved young Lucy and indirectly sent the culprit to his death with a spot of heavy-handed poetic justice. Huzzah!

Though Ripper Street is largely melodrama, there’s an enjoyably grimy undercurrent of humour running throughout it. In one of the funniest scenes so far, Jackson (Adam Rothenberg) found himself stumped by the chemical makeup of some mysterious medication and decided to just down it all, leading to him bouncing about the station, cheerily brandishing a gun in the face of startled newbie Hobbs.

Similarly light-hearted was the budding romance between ruffian with a heart o’ gold Drake (Jerome Flynn) and prostitute with a heart o’ gold Rose, while elsewhere, Reid was exchanging meaningful glances with the matron of the orphanage. We definitely smell a romance there.

This week was a great one for mystery fans as well, with a nice bit of CSI-ing at the murder scene, and an unexpected twist when we discovered Susan’s (MyAnna Buring) involvement in the murder. Though the villains of the piece were easily guessed within the first ten minutes, the journey to the denouement was great fun, piecing together bits and pieces from all over the shop.

Sinister Dr Crabb (Anton Lesser) cropped up to try and lobotomise people, Reid and Jackson came to blows and, as per, dogged reporter Best got on everybody’s nerves (but came in handy at the last moment).

Perhaps one of the most appealing things about Ripper Street is – aside from the consistently strong cast – the authentic touches. Jackson’s permanently bloody hands, the constant knocking back of gin, desk sergeant Artherton’s formidable ginger whiskers, and – most impressive of all – the Victorian slang and speech patterns, all give this series a real touch of class.

It might be a bit of sensational, pulpy fun but Ripper Street is very slickly done. Bring on next week!

Aired at 9pm on Sunday 20 January 2013 on BBC One.

> Order Ripper Street on DVD on Amazon.

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