Plutarch, Pelopidas
Bernadotte Perrin, Ed.

35. The death of Pelopidas brought great grief to his allies, but even greater gain. For the Thebans, when they learned of it, delayed not their vengeance, but speedily made an expedition with seven thousand men-at-arms and seven hundred horsemen, under the command of Malcitas and Diogeiton. [2] They found Alexander weakened and robbed of his forces, and compelled him to restore to the Thessalians the cities he had taken from them, to withdraw his garrisons and set free the Magnesians and the Achaeans of Phthiotis, and to take oath that he would follow the lead of the Thebans against any enemies according to their bidding. The Thebans, then, were satisfied with this; but the gods soon afterwards avenged Pelopidas, as I shall now relate.

[3] To begin with, Thebe, the tyrant's wife, as I have said, had been taught by Pelopidas not to fear the outward splendour and array of Alexander, since these depended wholly on his armed guards; and now, in her dread of his faithlessness and her hatred of his cruelty, she conspired with her three brothers, Tisiphonus, Pytholaüs, and Lycophron, and made an attempt upon his life, as follows. [4] The rest of the tyrant's house was guarded by sentries at night, but the bed-chamber, where he and his wife were wont to sleep, was an upper room, and in front of it a chained dog kept guard, which would attack everyone except his master and mistress and the one servant who fed him. When, therefore, Thebe was about to make her attempt, she kept her brothers hidden all day in a room hard by, [5] and at night, as she was wont, went in alone to Alexander. She found him already asleep, and after a little, coming out again, ordered the servant to take the dog outdoors, for his master wanted to sleep undisturbed; and to keep the stairs from creaking as the young men came up, she covered them with wool. [6] Then, after bringing her brothers safely up, with their swords, and stationing them in front of the door, she went in herself, and taking down the sword that hung over her husband's head, showed it to them as a sign that he was fast asleep. Finding the young men terrified and reluctant, she upbraided them, and swore in a rage that she would wake Alexander herself and tell him of the plot, and so led them, ashamed and fearful too, inside, and placed them round the bed, to which she brought the lamp. [7] Then one of them clutched the tyrant's feet and held them down, another dragged his head back by the hair, and the third ran him through with his sword. The swiftness of it made his death a milder one, perhaps, than was his due; but since he was the only, or the first, tyrant to die at the hands of his own wife, and since his body was outraged after death, being cast out and trodden under foot by the Pheraeans, he may be thought to have suffered what his lawless deeds deserved.