macbook pro thunderbolt cable to imac in target display. The imac also has a thunderbolt display. Will the macbook control all three monitors

I have a macbook retina and a imac 2012. I am looking at getting a thunderbolt display. I have currently my macbook retina connected to my imac and using target display when i need the other display. I am thinking of getting another display to use on my imac for when i need more room on my imac. My question is what will happen when i switch my imac in target display for my macbook. the ask a question person said my macbook will take control of all three but this other website said the thunderbolt would turn into the primary for my imac and the imac would be my secondary for my macbook. I was wondering if anyone knows for sure or can try it and tell me.