 By 2005 , Nesbitt had become tired of the formula and threatened to quit unless the structure of the series was changed . He was made a creative consultant and suggested that Murphy keep one undercover role for a full series , instead of changing into a new guise every episode . This new dramatic element to the series was intended to make it a closer representation of real @-@ life undercover work . Alongside his research with former undercover officer Peter Bleksley , Nesbitt hired a personal trainer and grew a handlebar moustache to change Murphy 's physical characteristics and tone down the " cheeky chappie " persona that the audience had become accustomed to from his roles . With his trainer , he worked out three times a week , boxing and doing circuits and weights . After the first new episode was broadcast , Sarah Vine wrote in The Times , " In the past , when attempting a nasty stare or a hard face , Nesbitt has never managed much more than a faintly quizzical look , hilarity forever threatening to break out behind those twinkly Irish eyes . But here , it 's different . He genuinely has the air of a man who means business . " The refreshed series marked another milestone in Nesbitt 's career ; he describes it as " a big moment " in his life . Murphy 's Law was not recommissioned for a sixth series , which Nesbitt attributed to the damage done to the fifth series ratings when it was scheduled opposite the popular ITV drama Doc Martin . 
 By 2005 , Nesbitt <a href='been_done' title='1'><mark>had</mark></a> become tired of the formula and threatened to quit unless the structure of the series was changed . He was made a creative consultant and suggested that Murphy keep one undercover role for a full series , instead of changing into a new guise every episode . This new dramatic element to the series was intended to make it a closer representation of real @-@ life undercover work . Alongside his research with former undercover officer Peter Bleksley , Nesbitt hired a personal trainer and grew a handlebar moustache to change Murphy <a href='null_genetive' title='2'><mark>'s</mark></a>physical characteristics and tone down the " cheeky chappie " persona that the audience <a href='been_done' title='3'><mark>had</mark></a> become accustomed to from his roles . With his trainer , he<a href='been_done' title='4'><mark></mark></a> worked out three times a week , boxing and doing circuits and weights . After the first new episode was broadcast , Sarah Vine wrote in The Times , " In <a href='None' title='5'><mark>the</mark></a><a href='negative_concord' title='6'><mark>past</mark></a> , when attempting a nasty stare or a hard face , Nesbitt <a href='been_done' title='7'><mark>has</mark></a> never managed much more than a faintly quizzical look , hilarity forever threatening to break out behind those twinkly Irish eyes . But here , it 's different . He genuinely <a href='got' title='8'><mark>has</mark></a> the air of a man <a href='null_relcl' title='9'><mark>who</mark></a><a href='uninflect' title='10'><mark>means</mark></a> business . " The refreshed series marked another milestone in Nesbitt <a href='null_genetive' title='11'><mark>'s</mark></a>career ; he <a href='uninflect' title='12'><mark>describes</mark></a> it as " a big moment " in his life . Murphy <a href='null_genetive' title='13'><mark>'s</mark></a>Law was not recommissioned for a sixth series , which Nesbitt attributed to the damage done to the fifth series ratings when it was scheduled opposite the popular ITV drama Doc Martin . 
By 2005 , Nesbitt done become tired of da formula and threatened to quit unless tdastructure of the series was changed . He was made a creative consultant and suggested dat Murphy keep one undercover role for a full series , instead of changin into a new guise every episode . dis new petty element to the series was intended to make it a closer representation of real @-@ life undercover work . Alongside his research with former undercover officer Peter Bleksley , Nesbitt hired a personal trainer and grew a handlebar moustache to change Murphy  physical characteristics and tone down thda cheeky chappie " persona that thedadience done become accustomed to from his roles . With his trainer , he done worked out three times a week , boxing and doing circuits and weights . After the dast new episode was broadcast , Sarah Vine wrote in The Times , " In no past , when attempting a nasty stare or a hard face , Nesbitt done never managed much more than a faintly quizzical look , hilarity forever threatening to break out behind those twinkly Irish eyes . But here , it 's different . He genuinely got the air of a man mean bizness . " The refreshed series marked another milestone in Nesbitt  career ; he describe it as " a big moment " in his life . Murphy  Law was not recommissioned for a sixth series , which Nesbitt attributed to the ddage done to the fida series ratings when it was scheduled opposite the popdar ITV drama Doc Martin .