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5/5 Matthew Oates meets a man for whom the purple emperor butterfly is a lifetime obsession.
4/5 Matthew Oates meets a biologist for whom slugs and snails are bread and butter.
3/5 Matthew Oates goes hunting for rare orchids and gets more than he bargained for.
2/5 Matthew Oates meets Rob Lambert to find out if there is any point to twitching rare birds.
1/5 Matthew Oates meets Andy Foster, a man obsessed by a rare and elusive beetle.