Tapper Watson and the River of Fire

Tapper and Fern are supposed to be living their best lives as interworld explorers on Colchis, but family stuff keeps getting in the way, and friendships are getting frayed. Then Tapper discovers an unimaginable new dimension - the River of Fire. But when their space sub, The Boldly Goes, braves the fiery new rivergate they find themselves somewhere strangely like the home they have all been missing. But nothing is quite as it seems. Can they get safely back again without being burnt to a crisp? Of course they can. Probably.