Denver is Missing was first published in 1971 and it shows. The gender stereotyping is typical of the era, and although Bette, the main female character, is strong, the general attitude is that she "does well for a woman". For all that, it's not a bad tale and the pages fly past quickly. Geologists on a ship drill deep into the sea bed and disturb a lake of nitrogen, leading to a disaster of the apocalyptic scale. Two of the party, Mitch and Bette, team up with Bill, a stiff upper lipped Brit, and his squeeze, Karen, to escape. Bill has a yacht and the foursome take to the ocean in an attempt to outrun the impending disaster. Despite the pretence of peril, it's all quite gentle really, although at the time (the 70s) I suppose it was more exciting. The author attempts to spice things up with the rescue of a feisty teenage survivor from a cruise ship, but it's unnecessary and lame. I've read a lot worse, and Denver is Missing turned out to be a bit of light entertainment an easy read that just about deserves its three stars.