The novel “Mortal Coil” is a clever chameleon that passes itself off as, variously, a thriller, a fantasy, a romance. But this splendid book is foremost a work of intensely considered philosophy, a metaphysical exploration of heaven and earth, reality and imagination, humans and angels. The author is Amnon Buchbinder, a Canadian screenwriter, director and film professor. Ergo, “Mortal Coil” is delightfully cinematic. The story, which is far too grand and multifarious to be neatly described, involves the life-or-death travails of Dr. Marti Powell, a doctor at a public clinic who develops extraordinary healing powers, thanks to a connection with what we’ll call, for shorthand, “the higher vibe.” Buchbinder is a very good writer. He’s an even better thinker. “Mortal Coil” — and its eloquent expression of complex ideas made simple — stays with you, inside you. Almost, you might say, like a secondary penumbra of energy.