The Dana Carvey vehicle Opportunity Knocks is an amiable but otherwise completely generic mistaken-identity farce. Feeling a special sense of déjà vu may be Robert Loggia, who plays the back-slapping CEO seduced by the fresh business ideas of an impostor (Carvey) -- in other words, the exact same role he played in Big. On the other hand, playing a slightly different role -- to good effect -- is Carvey himself. Too often pigeonholed as an impersonation comic, Carvey is not a good enough one to keep a movie afloat with impressions alone -- as was painfully evident in the 2002 stinker Master of Disguise. Here, he does do a couple funny voices -- the first President Bush and an Indian national among them. But much more often he's just a sympathetic everyman, and he's almost disarmingly likeable when free from his usual array of burdensome character affectations. As with most movies featuring a morally conflicted con artist falling in love with his mark, the script contains any number of moments when the ruse seems too thin to escape notice. But these are mostly tolerable, and the script's greatest sin is what it shares with the production on the whole -- being by the numbers in almost every respect. Sadly, this comedy may qualify as Carvey's best solo (i.e. non-Wayne's World) project, which says more about the SNL alum's lackluster film career than the strength of Opportunity Knocks.