What should I tell them?

I got laid off a few days ago. I was a content writer there, and the truth is the company wanted to hire video editors. They cameup with the decision to kick me out, with a lame excuse "poor performance", me and my other writing colleague did OT, and I was the TL. When I asked the HR for the reason for this termination, she told me it was due to poor performance, but after a day when I asked her the same question. Her answer differed! She told me it was due to "health conditions" and, i came to know it was all a planned movement! So, my question is when I'm appearing for the next set of interviews. What should I tell them when the other Hiring Team asks "Why did you leave the previous company?"