Mother Margaret was the abbess of the Prophet Elijah monastery in Menzelinsk, Kazan diocese. Under her strict and demanding, but at the same time loving guidance, the monastery prospered. It had fruit trees, kitchen-gardens, apiaries, and workshops for the production of icons and gold-weaving. There was even a photographic laboratory - an extreme rarity at that time.
In the late summer of 1918 the White armies left Kazan and the neighbouring towns, and Mother Margaret decided not to remain in the power of the Bolsheviks.
She was at the wharf preparing to leave when St. Nicholas appeared to her and said: "Why are you running from your crown?"
Stunned by the vision, Abbess Margaret returned to the monastery and told the monastery priest about what had happened. And sensing that she would soon have to suffer for the faith, she asked for her coffin to be prepared in advance, and that she should be buried on the very day of her death, after the burial service.
The next day Abbess Margaret was arrested as a "counter-revolutionary". They dragged her out onto the porch of the church during a service, and after refusing her request to commune of the Holy Mysteries, shot her. Immediately after the burial service, the sisters of the monastery buried her behind the altar of the church where she had been shot.
It was only the next day that the abbess's request to be buried on the very day of her death, which had at first seemed strange to the priest, became comprehensible. For the same chekists who had shot Abbess Margaret brought out a Muslim mullah to be shot, wishing to bury him in one grave with the Orthodox superior of the monastery. However, since she was already buried, they could not do this and took the mullah somewhere else.
A great Russian elder - St. Ambrose of Optina, it seems - prophesied about this monastery that under one superior they would build a church, another would be a martyr, and under a third - the bells would fall. The prophecy was fulfilled. Abbess Margaret became a martyr, and under the last superior they removed the bells from the church and closed the monastery.
In the 1970s, near the main church of the Menzelinsk monastery, which was closed at that time, they decided to dig a hole behind the very altar. Suddenly they came on a coffin. In it were the incorrupt relics of Abbess Margaret with a cross on her breast. They did not disturb the coffin, but filled in the grave and found another place for the hole...
(Source: A. Zhuravsky, Zhizneopisaniya Novykh Muchenikov Kazanskikh god 1918, Moscow, 1996, pp. 171-174; source)