Forgot to plug in my slow-cooker... Oi! Question about roast!!!?

I wanted to cook a pot roast for dinner tonight in my slow cooker. I did everything right except PLUGGING IT IN!!! I didn't realize until THREE HOURS later that I had neglected to plug it in! Is there a way that I can still have it ready before SIX hours of cooking??? Can I get away with putting the stoneware container in the oven for an hour and then finishing it in the crock pot so that it might still be ready in three/four hours? Please help! Dinner emergency!!! =(