By the light of the moon

the empty air as though he perceived
something of substance in it, he whispered not to Dylan, apparently
not to himself, either, but as if to a phantom visible only to him: 'By the light of the moon.'
    During most of his waking hours, Shepherd radiated strangeness
as reliably as a candle gave forth light. Dylan had grown
accustomed to living in that aura of brotherly weirdness. He had
been Shep's legal guardian for more than a decade, since their
mother's untimely death when Shep was ten, two days before Dylan
turned nineteen. After all this time, he could not easily be
surprised by Shep's words or actions, as once he had been.
Likewise, in his youth he had sometimes found Shep's behavior
creepy rather than merely peculiar, but for many years, his
afflicted brother had done nothing to chill the nape of Dylan's
neck – until now.
    'By the light of the moon.'
    Shepherd's posture remained as stiff and awkward as always, but
his current edginess wasn't characteristic. Though usually as
smooth as the serene brow of Buddha, his forehead furrowed. His
face gave itself to a ferocity he'd never exhibited before. He
squinted at the apparition that only he could see, chewing on his
lower lip, looking angry and worried. His hands cramped into fists
at his sides, and he seemed to want to punch someone, though never
before had Shepherd O'Conner raised a hand in anger.
    'Shep, what's wrong?'
    If the lunatic physician with a hypodermic syringe could be
believed, they had to get out of here, and quickly. A speedy exit,
however, would require Shep's cooperation. He seemed to be
teetering on the edge of emotional turmoil, and if he was not
calmed, he might prove difficult to manage in an excited state. He
wasn't as big as Dylan, but he stood five ten and weighed 160
pounds, so you couldn't just grab him by the back of his belt and
carry him out of the motel room as though he were a suitcase. If he
decided he didn't want to go, he would wrap his arms around a
bedpost or make a human grappling hook of himself in a doorway,
hooking hands and feet to the jamb.
    'Shep? Hey, Shep, you hear me?'
    The boy appeared to be no more aware of Dylan now than when he'd
been working the puzzle. Interaction with other human beings didn't
come to Shepherd as easily as it came to the average person, or
even as easily as it came to the average cave-dwelling hermit. At
times he could connect with you, and as often as not, that
connection would be uncomfortably intense; however, he spent most
of his life in a world so completely his own and so unknowable to
Dylan that it might as well have revolved around an unnamed star in
a different arm of the Milky Way galaxy, far from this familiar
Earth.
    Shep lowered his gaze from an eye-level confrontation with the
invisible presence, and although his stare fixed upon nothing more
than a patch of bare carpet, his eyes widened from a squint, and
his mouth went soft, as though he might cry. A progression of
expressions fell across his face in swift succession, like a series
of rippling veils, quickly transforming his grimace of anger to a
wretched look of helplessness and tremulous despair. His tightly
gripped ferocity swiftly sifted between his fingers, until his
clenched fists, still at his sides, fell open, leaving him
empty-handed.
    When Dylan saw his brother's tears, he went to him, gently
placed a hand on one shoulder, and said, 'Look at me, little bro.
Tell me what's wrong. Look at me, see me, be here with me, Shep. Be
here with me.'
    At times, without coaching, Shep could relate almost normally,
if awkwardly, to Dylan and to others. More often than not, however,
he needed to be guided toward communication, constantly and
patiently encouraged to make a connection and to maintain it once
it had been established.
    Conversation with Shep frequently depended on first making eye
contact with him, but the boy seldom granted that degree of
intimacy. He seemed to avoid such directness not solely because of
his severe psychological disorder, and not merely because he was
pathologically shy. Sometimes, in a fanciful moment, Dylan could
almost believe that Shep's withdrawal from the world, beginning in
early childhood, had occurred when he had discovered that he could
read the secrets of anyone's soul by what was written in the
eyes... and had been unable to bear what he saw.
    'By the light of the moon,' Shep repeated, but this time
with his gaze fixed on the floor. His whisper had fallen to a
murmur, and with what