It's certainly not one of his best performances. In fact, there are portions where he hams quite a bit. Yet, it won him an award at Filmfare for Best Actor in Negative Role. While that's debatable, Ajnabee is nonetheless an important film on Akshay's resume.
For one, he wasn't playing the good guy. If you look at his career graph, he's always played the virtuous do-gooder fighting for just causes. Or even if he was a good-for-nothing rascal, his heart would still be made of Bollywood-certified gold.
In Ajnabee, he plays a vile, manipulating crook with no ethics to redeem him. Luckily for him, the audience approved of this image change as well.
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