Perry Berg is president of Benthic Marine and a passenger aboard The Benthic Explorer, a 450-foot research ship endeavoring to drill into, and sample for the first time, the earth's magma core. Also onboard are the lovely Dr. Suzanne Newell; ex-navy commander and present submersible skipper Donald Fuller; and navy-cum-Neanderthal divers Richard Adams and Michael Donaghue. It is this cast of characters who, with the reluctant Perry, dive to the stilled drill site in order to make repairs. En route, they are sucked (or suckered) into a defunct undersea volcano and deposited into an otherworldly wonderland. That takes about 75 pages of fairly cogent spadework. The next 375 pages sprout some of the looniest, most derivative, made-for-TV-movie science fiction imaginable. Our heroes, you see, have been abducted to Interterra, an undersea world of staggering beauty and unheard of technologies--intergalactic travel and eternal life, for starters--populated by stunningly beautiful, toga-wearing, first-generation humans.