S4, E3: Martin thinks PC Penhale's much loved brother, Sam, has a rare genetic disease, but instead his findings change PC Penhale's opinion of Sam forever.

Starring John Marquez, Ewan Hooper, Martin Marquez
S4, E3: Martin thinks PC Penhale's much loved brother, Sam, has a rare genetic disease, but instead his findings change PC Penhale's opinion of Sam forever.