Will there be a fourth Dark knight movie?

It's a bit too soon to say with any certainty, but there are rumors that there may be another Batman movie.

The talk is that it won't be a sequel to The Dark Knight Rises, but may instead be a reboot as Christopher Nolan had already decided that Dark Knight Rises would close out the trilogy, tying up all the loose ends.

If there is a fourth movie, Christian Bale has apparently suggested that he would be willing to return, if Nolan were to approach him with a script.

This isn't the only chatter going around, there's also talk of a Catwoman spin-off which would star Anne Hathaway. Hathaway has said that she would be interested, but only if Nolan were to direct it.