the pairing does sound promising in theory ... but their lack of chemistry makes eddie murphy and robert deniro in showtime look like old , familiar vaudeville partners . 
(ROOT (S (S (NP (DT the) (NN pairing)) (VP (VBZ does) (VP (VB sound) (ADJP (JJ promising)) (PP (IN in) (NP (NN theory)))))) (, ...) (CC but) (S (NP (NP (PRP$ their) (NN lack)) (PP (IN of) (NP (NN chemistry)))) (VP (VBZ makes) (NP (NP (NN eddie) (NNP murphy)) (CC and) (NP (NNP robert) (NN deniro))) (PP (IN in) (NP (NN showtime))) (VP (VB look) (PP (IN like) (NP (JJ old) (, ,) (JJ familiar) (NN vaudeville) (NNS partners)))))) (. .)))
(ROOT (S (S (NP (DT ) (NN )) (VP (VBZ ) (VP (VB ) (ADJP (JJ )) (PP (IN ) (NP (NN )))))) (, ) (CC ) (S (NP (NP (PRP$ ) (NN )) (PP (IN ) (NP (NN )))) (VP (VBZ ) (NP (NP (NN ) (NNP )) (CC ) (NP (NNP ) (NN ))) (PP (IN ) (NP (NN ))) (VP (VB ) (PP (IN ) (NP (JJ ) (, ) (JJ ) (NN ) (NNS )))))) (. )))