December (18 page)

As Winter worked, we glided past villages built along the watercourse, and the wide barges moored beside them. Fairy lights dotted some of the houses, reminding us again that it was New Year’s Eve—a time for celebration. Rafe and I had both almost died on a small boat in Treachery Bay, exactly one year ago. I didn’t know if it was possible, but I could tell we were all silently hoping we’d be celebrating on the stroke of
midnight
, too.

With a bit more luck, now that Nelson Sharkey was going to present evidence against him, the Garda would hunt Sligo down before the night was out. Then Winter, at least, could resume a normal life, with him safely behind bars.

Further along, the tidal water rattled over the stones on the banks, as we passed a small
village
and smelt the fragrant scent of wood fires burning in the cottages. Stars twinkled through clouds.

A milky mist hung over the water, and the sound of the tide moving to the coast was all I could hear. The skiff followed the course of the river. We couldn’t really get lost—there was only
up
river or
down
river, and we knew we were heading in the right direction, looking out for the old St Mullins Bridge.

A chill, different from the frosty air of the night, shivered through my bones, registering a sudden danger alert. I shuddered, uneasy. As the countdown to midnight ticked away, danger was increasing, tensing like a coiled spring.

‘How are you going, Winter?’ I asked, as a distant town clock chimed six o’clock. We only had six more hours before the Singularity ran out, yet here we were,
still
trying to decipher the Riddle when we had three locations to search. Three! Slievenamon Castle, Cragkill Keep and Ormond Tower.

The secret of the Ormond Singularity
had
to be in one of the ruins, but we didn’t have time to search all of them.

Winter’s voice interrupted my thoughts. ‘It’s worrying me,’ she said, her face half lit by torchlight. ‘This misspelling of “ape”. I mean, I’d expect “aype” just like in “jaype”, not this “apye” with the “p” before the “y”. Scribal errors
happened
in copied texts, but you wouldn’t think it would happen in this Riddle. It’s so obvious that it should be spelled the other way.’

I caught a glimpse of Winter’s face. She was smiling.

‘What are you getting at?’ asked Boges,
pausing
over his oar.

‘What if it’s
not
a scribal error?’ I began, picking up Winter’s excitement. ‘What if it was
deliberate
? Is that what you’re saying? That the misspelling of “apye”
is
the “jaype” of the Riddle? Black Tom’s
trick
is that word itself?’

‘That’s
exactly
what I mean!’ Winter nodded vigorously. ‘That the error was made
intentionally
, so that the code would work! I’m going to check it right now!’

With the piece of vellum on her knees, Winter continued her decoding, focusing on the word ‘apye’, starting as she’d begun with the first words, with just one shift along the alphabet.

‘Don’t forget,’ began Boges, breathlessly
heaving
on the oars, ‘to look for “apye” in both lines of the alphabet. Apply it to the top line as well as the bottom line.’

‘You’re right,’ said Winter. ‘It could go either way. I’ll check both and see what they give us.’

‘From the top line, “apye” becomes “zoxd”,’ said Winter, shaking her head. ‘From the bottom line it becomes “bqzf”. No good. I’ll try two shifts along.’

‘OK, so with two shifts, from the top line, “apye” becomes “ynwc”,’ she sighed. ‘From the bottom line it becomes—’

‘It’s “crag”!’ I yelled. ‘It’s Cragkill Keep!
Winter
, you’re brilliant! Maybe the “double-key” code also hinted at the double shift needed to
decipher
“apye”!’

‘Careful,’ warned Winter, ‘you’re going to tip over the boat!’

Winter wrote out the last of the letters and now it was clear to see:

‘Bridge coming up! Six arches!’ yelled Boges, triumphantly. ‘The St Mullins Bridge! We’re almost there!’

Louder now, I could hear the clock chiming seven o’clock. We had five hours left to make it to Inisrue Marsh, find Cragkill Keep and search it. Winter’s map showed that Cragkill was on the right of the stone landing.

Ignoring my stinging hands, I hauled on the paddles as Boges and I swung back and forward in long pulls, sending the light cot scudding up the river. Ahead, a low stone wall rose from the river bank, leading to a stone wharf.

‘We’re here,’ I said, swinging the skiff towards the banks. ‘This must be the landing Ashling told us about.’

We worked hard, cutting across the tidal surge, then jumped out, dragging the cot up onto the stones, running it aground.

Boges swore at the cold but I was too excited to even notice it myself.

We hauled ourselves up the bank and onto
the landing. A small, sinking stone house with darkened windows was the only intact building I could see, but just past it, blocking out the night sky ahead, was the looming mass of a great ruin.

‘OK, we have to make our way along the bank to Cragkill Keep,’ said Boges, ‘which is further up on the right. Quick, follow me!’

Boges led the way with the sharp light from his torch.

Stay on the track, Ashling had warned. None of us wanted to end up sinking helplessly into the bog, like Rathbone had, but we dared to walk quickly along the narrow strip of firm, slightly raised ground that formed what we hoped was the safest path. On both sides of us, the
quicksand
of the marsh endlessly oozed into the dark, with only the occasional bare and struggling tree jutting out of its surface.

The chiming clock, louder still, rang out eight o’clock—it must have been in a nearby town. We’d been struggling along the muddy track through the marsh for over half an hour, and now we only had four hours left.

I paused. I’d heard something. I put up a hand to stop the others behind me.

Boges immediately doused his light. ‘What is it, dude?’

‘Listen.’

The darkness and silence of Inisrue Marsh surrounded us.

‘What are we listening to?’ whispered Winter.

‘I don’t know. But I get the feeling we’re not the only people on this track.’

I steadied myself and strained to listen again. ‘I swear I can hear footsteps,’ I whispered, as quietly as possible. ‘Ahead of us, coming this way. Can you hear it?’

This time, the others heard it too.

Flickers of light from torches in the distance became visible ahead of us. Low voices drifted along the chilly air.

We crouched low, unsure of what to do and where to go. I didn’t want to backtrack and lose ground, but I was worried we didn’t have any other option. Winter suddenly gasped beside me—now footsteps seemed to be coming from behind us as well! We were stuck in the middle!

Not knowing who was closing in on us was the worst part. I couldn’t even imagine who it could be; all I knew was that the intruders would be hostile. Hostile and desperate to stop us from uncovering the DMO first.

Then I recognised the loud voice ahead.

‘Sligo!’
Winter hissed, before I could.