Well, yes and no.
Here is one way that does achieve what you want (kinda): If you select the last text frame and cut it (Command-X on a Mac or the menu item Cut). You can immediately paste it back in place (Option-Shift-Command-V on a Mac or the menu item Paste in Place) and it will contain all the text that was originally in it but without the link to the previous text frame. The gotcha is that the previous text frame will now display the little red cross in its out-port indicating that there is overset text. You could, of course, do the same cut-and-replace for each of the other text frames in the series (including the first one) but that seems a tad tedious.
Here is a second way to break a thread that is not so good for your purpose: With the selection tool (black arrow), double-click on either the in-port of a text frame or the out-port of the previous text frame. Unfortunately, this empties the frame following the port you double-clicked and all subsequent frames (although subsequent frames, although now empty, remain linked to each other).
Here is a third way that is also not so good: With the selection tool, click either the out-port or the in-port where you wish to cut the thread. Then, with the cursor loaded (and showing the link icon) click in the text frame immediately up-stream of where you previously clicked. Again, the text frame immediately down-stream of where you cut the thread (and all subsequent text frames) will now be empty and the last filled text frame will show the overset text icon.
.
