This episode is a typically funny one throughout, but the scenes where Joey figures out the truth about Monica and Chandler rank up there with amongst the funniest the series has to offer. As others have noted, the expressions on Joey's face as he first starts putting two and two together, then the moment it all hits him, are simply hysterical. Chandler's wincing, then he and Monica corralling Joey into the bedroom to ensure his silence is very, very funny. I always thought Monica and Chandler's desire to keep their relationship secret was kind of silly, but their antics created many funny moments, so how can I complain.
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