Helen is a great white shark that marine biologist Ryan Johnson tracked along the coast of South Africa as part of a previous study of 50 sharks.
The study that traced the migration patterns of the species had concluded, but soon Helen and Ryan's worlds would meet again. Only, this time it would be in the most unexpected way and would go down in history.
I find out more from shark expert Ryan himself and take a closer look at one of the rarest ocean encounters ever filmed.