Angry Marching In Place

There have been several occasions where I have been laying in bed, watching tv, or just sitting around with friends, when my cat has gone to a soft object in the room and started marching in place on it. It's not the soft happy little knead like when they are on your lap and purring and massaging a blanket. My cat's pupils are quite large and he often looks at me and meows in a desperate manic way. I've done countless searches on the internet about this and no one seems to have the answer. I'm not scared I just would like to know what the hell my cat is doing.