Two timelines in the same English country house: 1809 and the present day. A teenage girl in the past anticipates chaos theory and thermodynamics. Researchers in the present try to reconstruct what happened and get everything wrong. Stoppard's best play is about the arrow of time, the limits of knowledge, and the way the waltz keeps going even as the universe runs down.

The case for it, the case against, and the rest of the canon open with Pro.