Wednesday, 6 October at 7.30pm on BBC One Wales
Dr Rhys Jones faces a completely new set of challenges as he goes into the back gardens of Kenya.
Here, the snakes he's hunting have already killed - so how will he cope when he's confronted by some of the deadliest snakes in Africa?
Rhys's Kenyan trip is one he's undertaken for many years as part of his work with the School of Biosciences at Cardiff University.
As well as giving his students a grounding in the biodiversity of the area, he is also helping to put Wales on the map as one of the potential saviours of the Northern White Rhino - of which only eight remain on the planet.
Rhys's work as a parasitologist and geneticist feeds into a programme designed to save the species, which has been poached and hunted to the point of extinction.
Aside from poaching, man's pollution of the world's oceans is having a disastrous effect on sea turtle populations.
Rhys helps some of the 1000's of turtles which have eaten discarded plastic bags by accident.
A mixture of laxatives and cod liver oil may not be to everyone's taste, but it could save a turtle's life - if Rhys can get to them in time...