The ElseWhere Chronicles

In this abbreviated episode, the much-reduced central cast mounts a twin assault on the Master of Shadows and the dark lake from which he and his teeming umbral minions have sprung.
The action picks up as Rebecca, Max and Theo follow enigmatic old Gabe to the high tower where the Master waits. There, they find a doppelganger of Rebecca that, according to Gabe, she must kill while the boys are dispatched to drop a flash bomb into the inky lake called the Source. Punctuated by snarky banter from the children and thunderous scenery-chewing by the adults ('You overreaching excel will destroy you, you poor fool!'), the ensuring battles bring only partial success for the mission. There are many spectacular explosions, heroic feats and last-instant rescues, though, as well as destruction on a truly grand scale. In contract to the at-best sketchy plotline, Bannister's atmospheric illustrations feature expressive characters placed in finely detailed, eerily organic landscapes or dim subterranean reaches inhabited by menacing swirls of shadow.
The lapidary art repays examination, but notwithstanding a prefatory thumbnail recap and later on-the-fly explication, new readers will get more out of this sometimes-dark series by taking the volumes in order. --Kirkus Reviews

-- "Journal"