NATURE versus nurture has been a topic of debate for decades and its complexity is probably one of the reasons Blood Brothers remains such a popular stage show.

Willy Russell’s funny but dark musical is now in its 28th year and although it has taken many forms, it remains true to the tale of twins being separated at birth he penned back in the early 1980s.

On paper, Blood Brothers appears a somber story of two ill-fated siblings born to an impoverished family, already with seven hungry mouths to feed, on Merseyside. But in true Willy Russell style, it is in fact quite the opposite and as Blood Brothers opened in Bath on Monday there was plenty of raucous laughter from the Theatre Royal audience.

Although tragic and poignant in places, the quick-witted script is often cause for great hilarity as we travel with Mickey (Sean Jones) and his twin Eddie (Mark Hutchinson) through various stages of their intertwined lives.

Sean Jones, as the Scouse ruffian of the pair who stays with his birth mother Mrs Johnstone (Maureen Nolan), is truly brilliant in the role and totally convincing at every age; from an enthusiastic cowboy-and-Indian-loving-eight-year-old to a pubescent and shy teenager right through to an anti-depressant-addicted ex-convict. Jones, who is no stranger to the role of Mickey having played the part when Blood Brothers left the West End last year, proves to be a remarkable and versatile actor who can adapt not only his age but his voice, demeanour and entire presence on stage within minutes.

Mark Hutchinson is also impressively changeable as the toffee-nosed and pampered twin Eddie, who was given away at birth to Mrs Lyons (Paula Tappenden) who despite her wealth cannot have the one thing she really wants.

Rather unfortunately, however, there is an obvious age difference between the two actors which made the idea that they were in fact twins slightly less believable. Equally hard to accept was how the unassured and impressionable Eddie could win the heart of streetwise Mickey’s childhood sweetheart Linda (Olivia Sloyan).

Maureen Nolan puts in an impressive performance as the put-upon mother whose love for both her sons never wanes. On stage throughout much of the three-hour show, she also has the majority of musical numbers to contend with and does so admirably despite the best of her singing days being behind her.

But it is headline star Marti Pellow, as the devilish narrator, who is sadly the biggest disappointment. His omnipresence on stage is justified, in that he represents both mothers’ consciences, but his melodramatic deliverance of every single word is not. Whilst his singing is naturally the strongest of the show, there is not enough of it and the Scot’s attempt at a Liverpool accent is unforgivable.

Blood Brothers is for the most part a very funny commentary on Liverpudlian life but at the same time asks many a difficult question over what right we have to decide our children’s fate and the what ifs of their social circumstance.

Much of this touring production was good enough for the West End but there were several aspects which, for me, just did not work. That said, there was standing ovation from the stalls of the Theatre Royal so clearly many think it worth a watch.

Blood Brothers is on at the Theatre Royal Bath until Saturday, February 2. Call 01225 448844 for tickets.