In a small theatre company, three actors, Priyanjali, Jorma, and Chiho are rehearsing for an upcoming play. On a particular day, the director, Yelena, scheduled a rehearsal for a scene involving a precious prop, a faux diamond necklace, which is crucial for the play's storyline. During rehearsal breaks, the necklace is supposed to be stored in a locked drawer to which only Yelena and the stage manager, Tendai, have keys. However, Yelena has been called away for an urgent meeting, entrusting Tendai with supervision.

Jorma, known for his forgetfulness, was last to handle the necklace during rehearsal. After the break, Chiho notices the necklace is missing. Priyanjali was busy practicing her lines and hadn't paid much attention to Jorma. None of the actors have been near the drawer where the necklace is usually stored. Yelena is unreachable, and Tendai had stepped out to speak to the lighting technician, leaving the actors alone on stage.

On Tendai's return, Chiho immediately tells him about the missing necklace. Priyanjali states she didn't see anything since she was engrossed in her lines. Jorma feels guilty but is unsure if he placed the necklace in the drawer before the break. While Tendai was the only person apart from Yelena with access to the key, he had been away only for the duration of speaking with the lighting technician and did not go near the drawer during that time. Tendai had also not noticed anything amiss with the necklace prior to the break, and no one else has been observed near the drawer.

Given these details, what can be deduced about who knows what regarding the situation with the missing necklace?
In this scenario involving the missing faux diamond necklace, there is a limited circle of individuals who may have information about its whereabouts or its status. Starting with Jorma, it is known that he was the last one to handle it during rehearsal, yet his forgetfulness and current uncertainty mean he is not aware of what became of the necklace after he last used it. He knows that he might have misplaced it, but without certainty, he cannot be considered aware of its true location after the rehearsal.

Priyanjali was preoccupied with rehearsing her lines and therefore did not attend to Jorma or the necklace. Hence, she has no knowledge of the activities surrounding the necklace during the period in question and cannot provide information about its current location or status post-rehearsal.

Chiho noticed the necklace's absence but possesses no knowledge prior to making that observation. Chiho knows that the necklace is missing but does not have any information about how it went missing or where it might be.

Moving on to Yelena, the director, she is currently out of reach at a meeting. Given that she was not present during the incident, she has no knowledge of the necklace's disappearance or its current whereabouts. However, she understands the rules about who has access to the necklace's storage as she is one of the key holders.

Tendai, who was responsible for supervising in Yelena's absence, temporarily left to talk to the lighting technician. He did not use his key to access the drawer within the timeframe of his departure and return. Therefore, Tendai knows he did not misplace or move the necklace during the time he spoke with the lighting technician, and he has been informed by Chiho of its current missing status upon return. This knowledge does not, however, extend to any certainty about what occurred during his absence or before it, only that he did not witness any irregularities before he stepped away and returned to find out from Chiho about the missing item.

Given these considerations, no person within the current group has full knowledge about the whereabouts or fate of the necklace post-rehearsal. Each holds a piece of the puzzle: Jorma with his last contact and forgetfulness, Priyanjali with her lack of observational input, Chiho as the discoverer of the missing necklace, Yelena with the absent knowledge, and Tendai with the knowledge of the post-discovery situation and awareness that he did not use his key during the critical period. Thus, while no one can claim full knowledge of the situation, collectively their individual knowledge and lack thereof suggest that the necklace was either misplaced by Jorma or an unobserved party has interfered with it, since there is no assertion from the present individuals that they interacted with the necklace during the critical time frame.