my cat has recently taken to leaping off my bed, where she sleeps during the day to catch the sun, as soon as I go in the room to 'hunt' what I hope are invisible prey.
I am fairly certain there is nothing uninvited living in the room as I have just finished decorating, including laying a new floor. This wasn't because of my cat trying to creep me out but her behaviour did encourage me to decorate now!
Not to dripfeed, we did have a mouse a few weeks ago that she did catch, and then play with under my bed from 1.30am until she lost it. I cornered the traumatised mouse later in the day and put it out of its misery. I found where it came in, I hope, and blocked up the gap.
She doesn't do the pretend hunting for anyone else, for them she rushes over and demands to be petted, me she just psyches out!
I just have to accept my cat has a weird sense of humour and thinks freaking me out is funny, don't I.