In the Gospel of Mark, Jesus’s enemies are named as follows: Pharisees, scribes, Herodians, elders, chief priests, the high priest. There is also one of his followers, Judas.
Here I suggest how costumes in the Gospel of Mark identified these roles to the audience during the performance of the play. The social identities or personal names of these persons were never revealed in dialogue. Rather, the audience was shown something visually distinctive; after that, anyone with whom those actors were friendly was also an enemy of Jesus.
The scribes were the intellectuals of the Pharisees. I suggest that these actors wore a distinctive fringed garment. Fringes were specifically commanded in Deuteronomy 22:12 “You shall make tassels on the four corners of the cloak with which you cover yourself.” Today this garment is known as a tallis/tallit and is worn by by many Jews on certain ritual occasions. I suggest that the garment was simply a himation, the basic cloak in Mark’s world, with (at least) four tassels. The scribes must have also worn/used some identification of their scribal role, like a pen case or a small scroll. They are the first of Jesus’s enemies to be shown to the audience, in Mark 2:6.
Then, when the scribes are accompanied by other actors who do not carry the prop designating the scribal role (2:16), the audience infers that the companions of the scribes are Pharisees. (Note: the scribes/rabbis of the Talmud were active in Mark’s time in Judea/Galilee (90s). However, Mark’s play is set some 60 years earlier. As the Temple was still in operation, the Pharisees were arguably considerably less popular among the peasantry than they would be a century later. So the presence of a fringed garment was distinctive of a Pharisee or scribe to both the world of the play and the world of the audience.)
The Pharisees consult with the Herodians (3:6). The Herodians have no distinctive qualities and are not members of the Council. They were probably added by an editor. (The Flavian court had welcomed the pro-Roman Herod Agrippa II and Berenice. Mark would not have insulted them by portraying “Herodians” as Jesus’s enemies.)
The chief priests were very likely otherwise known as Sadducees. The logic of the play implies that they were visually distinct from the Pharisees, and therefore I suggest that in the world of the audience Sadducees did not use a fringed himation (but possibly they used fringes in another way). Mark introduces them in 11:18, when they conspire with the already identifiable scribes.
The next group to be introduced is the elders. In 11:27 they are walking in the Temple with the (already identifiable) scribes and chief priests. The audience infers that they are a different group. Perhaps they have grey hair. (By the way, “a different group” was 2-3 actors.)
Now, having identified these groups to the audience, Mark has each of them address Jesus in the Temple: 12:13 Pharisees and Herodians, 12:18 Sadducees, 12:28 scribes. Jesus can now condemn “scribes” in dialogue at 12:35-40 (rather than answering a direct question) and the audience knows who he means.
In 14:10, a disciple sneaks away to to speak to the chief priests. No dialogue is needed to name or describe this disciple. The audience has already identified the chief priests as enemies of Jesus.
When that disciple appears onstage again, the audience knows that the enemies of Jesus now will be driving the action.
How does the audience know that the arrest party includes the servant of the high priest and not the high priest himself? Both master and slave would have worn fine garments, the Roman audience unfamiliar with the (now destroyed) Temple might not have recognized the props designating the high priest. The simplest explanation seems to me that the high priest is already (quietly) seated/enthroned in another part of the stage. Jesus is brought to him; he does not go to Jesus. The audience infers that the similarly costumed actor in the arrest party is only associated with the high priest.
In short, the absence of description in Mark’s narrative text is explained if he expected the readers/listeners to know that the narrative describes a staged performance. They filled in the visual cues themselves.