See Notes and Disclaimer in the first chapter.
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"A ghost? On the TARDIS?"
The Doctor didn't look up from the console. "Oh yes," he said. "I've often thought so."
"Why?" she asked.
He tapped another button. "The usual incidents; missing items, things left in one place and found in another."
"Sounds just like the TARDIS," Ace teased. "Why blame a ghost?" The Doctor didn't respond. "I've never seen it," she said after a moment.
"Hmmmm," murmered the Doctor. "Nor have I."
"What, you haven't gone looking?" That seemed unusual.
"No," he said shortly. "I don't think I want to find it."
Later, she realized he had his reasons.
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