1, the picture details found by netizen huangwei4050, Irene didn't drink poisonous tea.
2. After seeing moriarty, Irene noticed that the second cup of tea was poisonous, so she deliberately swallowed it twice (the film was close-up, and it was very artificial), making the professor think that she had drunk the tea, and then pretended to fall to the ground.
3. When moriarty told Holmes that Irene was dead, he picked up the chess queen, but after Holmes left, he put it back, indicating that Irene was not dead, and he knew that Irene was not dead.
By the way, moriarty may still be alive. ...