If you want to be completely immunized against all capitalist philosophy forever, I recommend The Destruction of Reason by Georg Lukacs.

He goes through the history of philosophy in Germany, taking apart each 'significant' philosopher in turn (Schelling, Schopenhauer, Kirkegaard, Nietzche, etc.) and showing that, at each stage, the philosophy being written (as well as the period in which it becomes popular) are entirely dependent on the psychological needs of the bourgeoisie in justifying and maintaining their rule at that specific moment in time.

He also shows at every stage how dialectical materialism is correct, and is the only true successor of the entire philosophical movement originating in ancient Greece. Just like communism is an evolution beyond the highest degree of capitalist organization, dialectical materialism is the evolution beyond the highest development of liberal philosophy (Hegel's dialectical idealism).

There is a price for this knowledge though, as the book is over 850 pages long.

If you want just a key slice, the chapter on Nietzsche is very good and gets across some key points, and is 'only' about 100 pages.