How to present cyclical data?

I need to present data 24 hours a day (the daily evolution of the value of a variable). The typical way to show this is a graph (bar, spline, …) that starts at "00:00" and ends at "24:00" (or variants of).

The data I have is intended to convey the idea that there are variations in a day that are repeated day after day. That's why I do not want to use an open graph where the ends are disconnected (the first point and the last point will be the same).

What would be a simple and reasonable way to show this to an end user?

This problem is similar to the classic maps (Mollweide projection, for example), where the Pacific Ocean ends on the right and resumes on the left of the map. In my case, the problem is simpler since this is just one variable.