দ্বিতীয় অধ্যায়: সন্দেহের জাল

It was nearly ten-thirty at night. The entire house seemed to have fallen silent, but inside Detective Rehan's mind, questions swirled like a tempest. Where had the diamond gone? Was the thief still within these walls? Or had the precious stone already been smuggled out? Rehan picked up the threatening letter again, donning gloves to examine it. On one corner, a faint fingerprint was visible. He immediately sent it to the police lab for analysis.

He then gathered everyone back in the drawing-room. They stood in a line: Alva, her face etched with worry; Larz, feigning composure; Ravi, the driver; Karim, the guard; Sohail, the gardener; Shamsuddin, the cook; and the two housekeepers. Rehan’s gaze swept over them slowly. "I will not be making any arrests tonight," he announced. "But I am certain the thief is standing in this very room." A ripple of unease passed through the group as they exchanged glances.

Just then, Rehan noticed fresh sweat beading on Larz’s forehead. He remained silent, however, and instead turned to Ravi. "Where were you last night, after midnight?"

"In the garage, sir," Ravi replied.

"Did anyone see you?"

"Karim, the guard." Karim corroborated Ravi's statement. Rehan then addressed the gardener. "And you?"

"I went to sleep in the staff quarters at ten last night," Sohail said.

Rehan meticulously noted down everyone's alibis. Suddenly, he declared, "Mr. Larz, I'd like to see your office once more." Larz’s face paled instantly. "Of course... please, come this way."

Inside the office, Rehan surveyed the surroundings: the bookshelves, an expensive clock, an old wooden desk, and a large picture hanging on the wall. His eyes were drawn to the picture. It wasn't hanging perfectly straight; it was slightly askew. Rehan took it down. Behind it was a small digital safe. Everyone’s eyes widened in surprise.

"That's an old safe," Larz said quickly. "It hasn't been used in years."

Rehan said nothing. He instructed them to open the safe. Inside were some old papers, a few foreign coins, and a black cloth. The diamond was not there. But as Rehan picked up the cloth, he paused. It was the kind of fabric that could easily wipe away fingerprints. He confiscated it for examination.

Just then, his phone rang. It was the lab. The fingerprints from the threatening letter did not match any of the household staff. The letter, therefore, had been written by someone whose prints were not on file with the police. The mystery deepened.

As the night grew late, Rehan made a deliberate announcement: "I will be returning home tonight. I'll be back tomorrow." Everyone assumed the investigation was temporarily over. But Rehan, after leaving the house, crossed the street and ascended to the roof of an empty building. Through his binoculars, he began to watch.

It was one in the morning when he saw it. The back door of the house creaked open slowly. A figure clad in black emerged, moving with extreme caution. A small torch beam cut through the darkness. The person scanned their surroundings before walking towards the garden. Rehan quickly alerted the police via his walkie-talkie and then, silently, began to follow the figure.

The person knelt in a corner of the garden and started digging. Suddenly, Rehan shouted, "Don't move!" The figure startled and bolted, a thrilling chase ensuing across the garden, over the gate, and onto the dark street. But the police had anticipated this, surrounding the area. As the figure's mask was removed, everyone gasped. The face revealed was one no one had ever expected.