Beyond the Mountains of Madness - Brian Stableford - Bog

When Tom Andersley returns to his family in Yorkshire after World War I, he is a changed man. Unable to connect with others, he becomes obsessed with working on experiments in cross-breeding fruit trees. Then an old friend, Lawrence Oates, visits him. The odd thing is, everyone believes Lawrence died in an Antarctic blizzard years ago. Perhaps more odd, Lawrence explains that he was preserved by aliens--aliens now under attack from mysterious adversaries. And they need Tom's help and his expertise in plants in order to win their war.