Is Gravity spanning the fifth dimension?

This is the type of scientific musings that captures my interest, however I can’t comprehend it. I was listening to a podcast which mentioned that gravity is a lot weaker than the electromagnetic forces. The physicist postulated that the perhaps the majority of gravitational force was being expressed in the 5th dimension. If we were 2 dimensional beings (flatlanders) then something moving along the third dimension would only appear to us when it intersected our x and y axis. We would see it as a flash. But I can’t get my head around a force that exists partly in our 4 dimension space (including time) and partly in the 5th dimension. If someone can help me out with this, add a comment.

PS – I think the dimension count is about 13 so we can cover UFO’s as inter-dimensional space in another posting.