The Doctor and Evelyn arrive at the Galapagos Islands, finding a young naturalist named Charles Darwin conducting research and observations there. The Doctor is a bit worried about Evelyn interfering with the development of Darwin’s theories, but he soon has more to worry about – prisoners at the local jailhouse disappear without a trace, and a woman is upset that her brother, whose mind has snapped after what he says was an encounter with “devils,” is scheduled for execution. Though the Doctor is less than impressed with the local governor’s demeanor, he soon realizes that something far more sinister is at work here – a small enclave of hibernating Silurians has awoken in their chambers deep below the islands, and one of them is plotting the destruction of homo sapiens… which may only be fair, since he created homo sapiens.
written by Jonathan Morris
directed by Gary Russell
music by Alistair LockCast: Colin Baker (The Doctor), Maggie Stables (Evelyn), Miles Richardson (Charles Darwin), George Telfer (Captain Fitzroy), Julian Harries (Governor Lawson), Daniel Hogarth (S’Rel Tulock), Helen Goldwyn (Scientist Shvak), Jane Goddard (Greta Rodriguez), Jez Fielder (Lokan)
Timeline: after The Apocalypse Element and before Project: Twilight
LogBook entry and TheatEar review by Earl Green
Review: I’ve always loved the Silurians, especially their first appearance in Jon Pertwee’s second story in 1970. Their sinister, low voices, that creepy third eye that can kill a human being from across a room, and that nagging moral question over whether they still have a claim to Earth after going into hibernation millions of years ago. That morality plays perfectly with Colin Baker’s Doctor; Baker does righteous indignation and moral dilemmas better than any of the other actors who have steered the TARDIS, and Bloodtide is a real gem of a sixth Doctor adventure. Maggie Stables also holds her own as Evelyn, spending much of the story not with the Doctor but with young Charles Darwin.
If there’s anywhere that Bloodtide fails to deliver, it’s the character of Greta. Now, I try to be constructive in my criticisms of Big Finish’s Doctor Who audio plays, not only because I sincerely want them to succeed in doing Doctor Who in this medium but because I also know that at least a few Big Finish writers and others have read this site’s reviews. That said…Greta may be the worst written and worst voiced character in the history of Big Finish’s audio adventures. A supremely annoying vocal interpretation (in the form of an almost-mockingly stereotypical quasi-Spanish accent) and a below-par characterization (hearkening back to the helpless, screaming female companion roles of 1960s Doctor Who) made for – in my opinion – an immense annoyance factor in the story’s first two episodes. (I was actually very relieved when the character of Greta made a quick exit at the beginning of episode three.)
The Silurians are expertly recreated in their original form – low, menacing processed voices, and the signature sound effects of their 
deadly third eye. These are the Silurians from 1970 who scared the hell out of me when I saw the rerun of their debut story in my early teens. The stuff of nightmares – Doctor Who monsters at their best, and yet always with that oddly sympathetic edge that keeps them from really falling into that classic monster mold.
Bloodtide is an excellent adventure; it sidesteps the mistakes of 1984’s Warriors Of The Deep and recreates some of the better beats of Doctor Who And The Silurians, while also doing the Doctor-meets-figure-from-history schtick that Colin Baker’s era did extraordinarily well. It’d all be an excellent, first-rate story…but alas, poor Greta.