Thank you for your help, Tom. The first frame is me doing a specific action. It doesn't begin in black. And the problem frame is from 10 seconds in. It doesn't appear in the timeline at the beginning - only up in the edit window, when I highlight the video to edit, or even when I put the skimmer at the beginning of the video. When I put the skimmer at the beginning, the problem frame fills the edit window and has a reversed transparent L in the lower right hand corner. I wanted to trim the beginning and end of my video, so I highlighted the clip and used the arrows to drag and trim successfully. But when I did that, the split-screen in the edit window (sorry if that's not the right term for it) shows the problem frame on the left and (as it should) the footage being trimmed on the right. It used to show the beginning of the video on the left. Once it's rendered and I play the video on my desktop, it begins where it should, but the freezeframe that represents the video is the problem one, not the 1st frame from the video. I hope I'm making sense. Thanks again for your help.