Pretty much all the Die Hard movies had good evil plans, but I especially liked the third.
Where Eagles Dare has wonderfully twisted plan in it, though it's carried out by the goodies rather than the baddies. First you orchestrate the crash of a plane with a fake general on board so that he gets captured by the Germans to give you an excuse to send a group of commandos to rescue him. Then the team lets itself be captured as well, prompting the three German moles deliberately placed on it to reveal themselves. The leader of the commando team then claims to be a German agent as well, as evidenced by a high ranking German officer vouching for him and by the fact that he knows the name of the top German agent in Britain. He claims the three moles had been discovered by the Brits (true) and replaced (false). To prove their identity, the three moles write down the names and addresses of all the German agents in Britain that they helped recruit into three notebooks. The commando leader, in fact a triple agent working for the British and feeding false or outdated information to the Germans, then seizes the notebooks, the actual objective of the entire operation, and makes a daring escape. While on the plane home he confronts his commanding officer, who selected him to lead the rescue team in the first place. The British had suspected him for some time, they asked him to choose a leader for the rescue team and he chose the triple agent because he believed him to be a German double agent, a seemingly perfect choice. The leader of the rescue team presented his name as the top German agent in Britain as evidence of his identity and its acceptance was proof that the suspicion had been correct. Now wasn't that just deliciously convoluted?