‘What?’ cried out Cornelius, aghast, and Harriett flinched at the stab of sound. He looked contrite and allowed her to recover before she went on.

‘That day, when I woke with one of my headaches, Charlotte must have known that I would be retiring to bed before my usual time. We went out for an early walk in Hyde Park to get some air. The streets are at their quietest then, and when we passed the pillar letter box by the church she posted a letter. She tried to distract me by drawing my attention to the flower beds but I saw what she did, and when I asked about it she said it was a note to Mr Martin. That night I retired to my room at six o’clock and did not rise again until six the next day. I did not see Charlotte in all that time, but next morning she was so upset that she confessed what she had done. She told me she had put the knife in the flower urn, she said it was covered in blood and she dare not put in her pocket or she would stain her clothes.’

Cornelius hid his face in his hands and groaned.

‘And she took the watch so the motive of the crime would appear to be robbery?’ asked Sharrock.

‘Yes.’

‘What did she do with it?’

Harriett fidgeted and her eyes flickered nervously about the room. ‘She knew she could not sell or pawn it. She threw it away.’

Frances had been watching the eyes of the trapped woman. She rose and went to the writing desk and tried to open the drawer, but it was locked. ‘Please let me have the key to this drawer.’

‘I don’t have it. Perhaps Charlotte has it.’

Frances turned about and came to face her. ‘I’m afraid I don’t believe you. In fact I don’t believe most of what you have been saying to me for the last month. I am going to have to search you.’

Harriett recoiled. ‘Please, no,’ she whispered.

‘I think you would prefer it to the Inspector searching you, which I am sure he is prepared to do.’ Sharrock looked alarmed at the suggestion but said nothing. ‘Or to avoid any searches, kindly give me the key.’

‘Harriett, I beg you,’ said Cornelius, ‘we must have this resolved. For the sake of decency give Frances the key to the desk. If you cannot then I will force the lock myself.’

Harriett hesitated and, without meeting the gaze of anyone in the room, took a key from her pocket and handed it to Frances. Cornelius smiled in relief, took Harriett’s hand and patted it gently. ‘Don’t worry; all will be well, I am sure of it. There has been a terrible mistake. Frances will find the answer, she always does.’

‘You are such a good kind man,’ murmured Mrs Antrobus, gazing up into his face, her eyes bright with tears, and Cornelius, like so many men before him, was unable to do anything but melt in sympathy.

As Frances unlocked and opened the drawer the Inspector hurried to her side and peered in. ‘Aha!’ he said, loudly enough to make Mrs Antrobus wince.

Cornelius cupped his hands protectively over Harriett’s ears. ‘Please – this lady has suffered enough.’

Frances stood back, and Sharrock delved into the drawer, removed a silver watch with a broken chain and held it up. ‘That should match the portion of chain found on the body, and if I am not mistaken, we have an engraving here – J.E.’

‘Charlotte gave it to me, she told me to hide it,’ whispered Harriett.

‘Was that before or after she threw it away?’ retorted Sharrock sarcastically. ‘Mrs Antrobus, I am arresting you for the murder of Jonathan Eckley —’

‘No,’ Harriett wept. ‘Please don’t put me in a cell, I couldn’t bear it.’

Cornelius stared at her in horror. He let go of her hand, rose and looked at the watch. ‘There can be no doubt?’

‘None,’ Sharrock assured him. ‘This is the murdered man’s watch. If Miss Pearce didn’t kill him then Mrs Antrobus did, and my money is on this lady here. Why don’t you call a cab, sir, and we can take her to the station?’

‘Please – no,’ begged Harriett.

‘Inspector – Uncle – might I suggest something?’ Frances interrupted. ‘I think in this very particular and unusual case it would be better if Mrs Antrobus was not taken to the police station but placed in some other secure custody, somewhere that would not be torture to her. A sanatorium, somewhere quiet. You could employ suitable women to guard her.’

‘I don’t have armies of women at my beck and call to guard special prisoners,’ argued Sharrock, ‘neither do the police have limitless monies for fancy sanatoriums.’

‘I am sure some arrangement could be made. Would you consider it? Uncle, can you help?’

Cornelius hesitated and then gave in. ‘Very well, for Charlotte’s sake, I will see what I can do.’

‘I don’t know, it’s very irregular,’ Sharrock grumbled.

‘Please,’ Harriett begged again, ‘please don’t take me to that awful place.’

Sharrock looked dubious.

‘Perhaps,’ Frances went on, ‘the police would be willing to make a special case if, in return, Mrs Antrobus was to make a full confession of her crimes – all of them?’

‘All of them?’ bellowed Sharrock. ‘How many are there?’

Harriett, with her hands over her ears, moaned ‘Yes, yes, I will confess, only please everyone be quiet.’

‘Let us all calm down and sit quietly,’ agreed Frances.

The company was seated but no one in the room rested easy. Cornelius dragged his hands distractedly through his hair. ‘What other crimes?’

‘The murder of Charles Henderson and the murder of her husband.’

Harriett wiped her eyes. ‘Please fetch me some water. I will do as you say.’

‘I don’t understand this at all,’ sighed Sharrock, ‘but I am sure Miss Doughty will explain, as she usually does.’

When Mrs Antrobus was given a refreshing drink, and the Inspector and Cornelius were quiet and attentive, Frances began.

‘This is what I think happened. The two misses Pearce, Harriett and Charlotte, were the daughters of the Antrobus brothers’ senior assistant, and when Mr Edwin became fascinated by the younger sister it was very good fortune for her. But his brother, Mr Lionel, was unhappy about the match. It would be some years before Edwin Antrobus could make a sufficient fortune to marry, and Miss Harriett must have feared that his brother would find some way of preventing it. Mr Edwin was, however, the principal heir of his uncle, Charles Henderson, who had willed him this house and its furnishings and some investments. With such a handsome legacy the couple would be able to marry at once. But Mr Henderson was only thirty-seven and, apart from his headaches, in good health.

‘On the night of Mr Henderson’s death he had gone to get a key to his study to show the company his collection of snuffboxes. Mrs Pearce was feeling unwell, and Harriett took her mother into the parlour to look after her, but having settled her mother there, I think she hurried up to the study where she flattered Mr Henderson into showing her the pistol and how it was loaded. She must have been shown the study on an earlier visit and knew the gun was kept there. I expect she asked to hold the gun, promising to be careful. Then she shot him. She had only time to run into the nearest room, the bathroom probably, to hide, which was why the study door was found open. Edwin Antrobus rushed up the stairs and found his uncle’s corpse. Harriet stayed in the bathroom until he had gone down to tell the others what had happened, and while he was so engaged she managed to creep downstairs to rejoin her mother in the parlour, who was sufficiently unwell that she was easily persuaded that her daughter had never left her side. I do wonder if Mr Henderson’s Aunt Lily, who had gone to look for the key and was in the hallway at the time her nephew was killed, knew more than she was able to say. Perhaps she saw the murderer creeping downstairs. But the shock was so great that she was a broken woman and died soon afterwards.’ Frances glanced at Harriet, who was icily calm. ‘How did Aunt Lily die?’