Towards the end of the first half, when the trip to Europe is over and SRK and Kajol are saying their goodbyes in the railway station, Kajol asks SRK if he would come to her wedding. And SRK simply smiles, shakes his head as if to say no, and walks away.
Aditya Chopra sets that scene up well: he's spent half the movie getting them to fall in love. A few scenes earlier, SRK proposes to Kajol and, seeing her shocked expression, laughs and says he was joking. He builds it all up to that moment in the railway station - in that one look, without a single line of dialogue being spoken, he tells her that the earlier proposal was no joke, he really does love her. Beautifully done. The rest of the movie is standard, albeit well-made fare for its genre, but for one moment there, the movie has more intelligence than the average glossy romance.