Ladybird Books was a children's book publisher. First publishing in 1914, Ladybird were most famous for their fairy tale books, as well as educational books. In the 1980s, Ladybird turned their attention to publishing books based on the more popular children's franchises, such as He-Man, Transformers and Action Force.
Autobot Hostage was published in 1988 by Ladybird. The book was the first and one of only 2 books published in that year, for the Transformers line. It was written by John Grant and illustrated by Glenn Steward. Aside from the single book release, there was also a "Tell-A-Tale" version released, that came with a cassette tape, narrated by Peter Marinker. The tape also had music and sound effects.
The plot for the book is While on patrol on Nebulos, Highbrow is captured by Tentakil and brought before Scorponok, who intends to ransom him for Optimus Prime himself. Naturally, though, Prime suspects treachery from the Decepticons, and secretly carries Fizzle and Hosehead in his trailer as he heads out the Decepticons' mountain base. Met on the way by Spinister, Prime hides beneath a rocky overhang long enough to allow Fizzle and Hosehead to slip away unseen, before surrendering to Dreadwind and Darkwing. Scorponok seals Prime in a cave with a mega-voltage electrical field, and reveals Prime’s suspicions to be true – he has no intention of releasing Highbrow, or any of the other Autobots who should come after him.
Out in the mountains, Fizzle and Hosehead discover Highbrow, but he does not react when they call him, or even when they fling rocks at him. Hosehead’s Nebulan partner goes in to investigate and discovers an immobilisation device attached to Highbrow's back; with it removed, Highbrow joins the others to rescue Prime. Hosehead is able to short out the electrical field holding Prime with his water pumps, and Fizzle holds off Decepticon pursuers with a jet of flame from his exhaust. Scorponok opts to fight fire with fire and calls in Cindersaur, but the Firecon’s flame-breath is defeated by Hosehead’s water jets, and the Decepticons are left stumbling around in a cloud of smoke as the Autobots make good their escape.
Thanks to RetroRobotRadio for uploading the audio book and scans. The book appears to be taking inspiration from the Marvel comics of that year, with Optimus Prime in his Powermaster form leading the Autobots and Scorponok leading the Decepticons, though it's not explained how he went from mindless drone to actual sentient leader. We have a classic Transformers tale in this one, that could have easily found home in the cartoon.