The edition of Seventeen Swords《風雲十七劍》I have was written by Hong Kong wuxia author Huang Ying 黃鷹 and published in 1982. It’s short, only eight chapters and one volume. The following is a brief plot summary, translated from one I found online.

Synopsis

Three years ago, seventeen of the jianghu’s most famous assassins suddenly teamed up to take on an assassination mission no killer had dared try before, and launched a series of assassinations that shook the jianghu. For the past three years many died within the jianghu and everyone was uneasy, including the three powerfu Nangong, Ouyang, and Sima families.

Nangong Ling was the head of the Nangong family, Ouyang Xiao’s elder brother Oiyang Tie, and Sima Rulong’s son Sima Chengfeng were all assassinated. The three families then got together to hatch a plan of revenge on the seventeen assassins. They managed to kil thirteen of them. Only the famed Ghost Scholar, Black Raksha, and Red Tassel Regalia Marquis had not been found, and the only clue was that the leader of the seventeen assassins was a mystery.

Ghost Scholar accepted an assassination assignment; the target was Ye Guhong—a handyman at Myriad Sword Villa, a person not versed in the Classics, nor related to any of the three major families of the wulin. But the strangest thing was: it had been secretly commissioned by Red Tassel Regalia Marquis.

Sima Zhi of the Sima family investigated all the way to Ghost Scholar Shen Guiyu’s secret hideout and learned that his next target was Ye Guhong, and before he died he wrote a letter in blood. Back at the three families, Nangong Su, Ouyang Chang, and his four disciples decided to go to Myriad Sword Villa to tip them off, but Black Raksha spied on them and learned of their plan. Black Raksha went to Myriad Sword Villa as well, intending to kill them all so that Ghost Scholar could carry out his assignment to assassinate Ye Guhong.

Myriad Sword Villa could be said to be the sould of the wulin of the Central Plains. Thirteen years before there was a big, bloody fight there among the various sects that raged for three months and resulted in many casualties and sapped a lot of the wulin’s vitality. Only the Triple Crown Palace stayed out of it, but the head of Triple Crown Palace, Gongsun Wuwei acted as a mediator and finally put an end to that wulin catastrophe. However, of the 140 disciples of Triple Crown Palace, only three remained. Half of the sect heads felt guilty and the other half were moved by Gongsun Wuwei’s righteousness, so they each sent disciples to Triple Crown Palace to train, nearly ten-thousand in all, as a display to indicate that all the world is one family, and thenceforth there were no more quarrels. Triple Crown Palace thereupon changed its name to Myriad Sword Villa.

Myriad Sword Villa would not accept someone as a disciple who did not reveal his or her background. This was originally Triple Crown Palace’s rule. To become Gongsun Wuwei’s disciple one must be from one of the major sects, and one must have a recommendation letter from your sect head as well as a letter of trust.

Gongsun Wuwei only had three disciples who had entered the master’s study as advanced disciples. One was called Hang Chunhua, another Gao Yong, and the third was Sima Rulong’s daughter Sima Qing’e. Ye Guhong actually was also secretly one of Gongsun Wuwei’s advanced students, but only Guhong and the master himself knew this.

Ye Guhong had joined Myriad Sword Villa when he was seven and at that time did not belong to any sect. He had shown up outside the gates of the villa, starving and hard-up. Gongsun Wuwei found him there, rescued him, and allowed him to stay on. Gongsun Wuwei saw that Ye Guhong had a good foundation, so he secretly broke his own rules and admitted him enter the master’s study as an advanced student and secretly taught him martial arts, though in front of others Ye Guhong was instructed to hide his martial arts ability and his position as an advanced student.

Gongsun Wuwei was famous throughout the jianghu for being strict but fair. He knew it was inappropriate to secretly take on a student, and he also knew it was unfair for Ye Guhong to have to conceal his identity and sink to that of an underling, and so he called in Ye Guhong and advised him to leave Myriad Sword Villa as soon as possible.

Ghost Scholar and Black Raksha arrived outside Myriad Sword Villa and killed Ouyang Chang and his disciples, though Nangong Su managed to get away only injured. She ran into Ye Guhong went she went into the villa and she told him that Ghost Scholar and Black Raksha were looking to kill him, and that Red Tassel Regalia Marquis was nearby as well, so he ought to be very careful.

Nangong Su told Ye Guhong to take temporary refuge with the Shangguan family. Ghost Scholar pursued him there to kill him, and Ye Guhong was forced to reveal his martial arts ability and drive Ghost Scholar off. At this time there was another master of the wulin watching off to the side, LOng Zaitian, and he was itching to show off and compare his skills to Ye Guhong, who had to be conciliatory and let him have a bout.

Gongsun Wuwei’s senior disciple, Hang Chunhua and his junior sister Sima Qing’e had an affinity for each other and decided to go to Sima Rulong, who was at the Shangguan residence at the time, to propse marriage. When they got to the Shangguan estate they found Long Tianyou there and he had been talking frivolously about her. Sima Rulong also told them that Sima Qing’e had been betrothed to Long Tianyou by her parents when she was a child. Sima Qing’e opposed this for the sake of her own happiness. Hang Chunhua and Long Tianyou made a bet: whoever was first to kill one of the remaining four assassins could marry her.

Once Ye Guhong and Nangong Su arrived they unexpectedly saw senior brother Hang Chunhua there and they were delighted. Hang Chunhua had a lot on his mind, though, and he got drunk with Ye Guhong and talked about it with him. By the time Hang Chunhua was nearly falling over drunk, he went back to his room to rest while Ye Guhong went to the courtyard, still drunk. In the morning when he woke he found Long Tianyou’s throat had been pierced by a sword and was laying dead beside him. The nightwatchmen all said that no one had intruded last night so they didn’t know who the perpetrator was.

Just then, Long Tianyou’s father, Long Zaitian paid a visit to the Shangguan estate and learned the sad news. He pointed out in front of everyone that Ye Guhong knew martial arts and that he was adept at it, leading Ye Guhong’s cover up to make him the most suspicious as murderer. He was surrounded by everyone, but luckily Nangong Su shielded him so he was able to get away.

The three assassins at this time put their ruse into action. Black Raksha went disguised as Sima Qing’e and killed Sima Rulong. Ghost Scholar used some tricks and killed Nangong Ling and Ouyang Xiao. And Red Tassel Regalia Marquis went to where Nangong Su was being kept under house arrest to kill her, though in a freak combination of errors he ended up killing his true love, Sima Qing’e. Turns out that Red Tassel Regalia Marquis was actuallg Hang Chunhua. He knew long ago the secret between his master and Ye Guhong and was afraid he would lose his position as the senior disciple to take over the sect in the future, so he had commissioned Ghost Scholar to kill Ye Guhong, one to retain his position, and two so that when they were fighting he could get a look at Ye Guhong’s fighting moves.

Hang Chunhua was so grieved he wanted to die, so after he buried Sima Qing’e, he had a final fight with Ye Guhong and Nangong Su. Hang Chunhua was finally killed, and he left behind a name locket after his death that exposed the identity of the leader of the seventeen assassins. But who was the leader…?

There were five words engraved on the name locket, each word like a needle in Ye Guhong’s heart.
—Myriad Sword Villa Gongsun Wuwei!

So it seems like a typical whodunnit mystery wuxia which was made popular by Gu Long, who in turn was influenced by both wuxia author Sima Ling as well as Japanese mystery writers.