'In case' or' in case of' mean if something should happen or happen to be. 'In case' is usually followed by a clause 'We'll take an umbrella in case 'it rains' 'In case of' is followed by a noun. 'We'll take an umbrella in case of 'rain'. 'In the case of' is used to introduce a particular example, instance or occurence. 'There are new developments 'in the case of' the Libyan woman who was raped.'

In case: Fire is very dangerous. In case of emergency, use the fire extinguisher. In the case: Robbery is done by people who wants to have something valuable. But in the case of John (for example) he robs for his family. See the difference? :D Try to visit this: http://www.merriam-webster.com/dictionary/incase