| Actor | Role |
|---|---|
 Tim PreeceAlfred Russel Wallace | Alfred Russel Wallace |
 Tony SteedmanCharles Darwin | Charles Darwin |
 Patrick AllenSir James Brooke | Sir James Brooke |
| EEric DodsonSpenser St. John | Spenser St. John |
 John HorsleySir Charles Lyell | Sir Charles Lyell |
| NNeville BarberJoseph Hooker | Joseph Hooker |
 Alexander KnoxThomas Bell | Thomas Bell |
| CCelestine RandallEmma Darwin | Emma Darwin |
 Jan HarveyFanny Sims | Fanny Sims |
| AArthur BlakeMr. Stevens | Mr. Stevens |
| PPaul HargreavesCharlie Allen | Charlie Allen |
| JJamaluddin JalilAli | Ali |
| MMichael BurrellKew Botanist | Kew Botanist |
| DDennis EdwardsMuseum Curator | Museum Curator |
| DDennis 'D.J.' JenningsAbbey Canon | Abbey Canon |