As casting begins for the sixth season of Marvel's Agents of S.H.I.E.L.D., new character breakdowns offer some clues on where the ABC series may go next.

The inaugural Marvel Cinematic Universe television series began principal photography this week for a 13-episode season scheduled to premiere next summer. The first round of new characters for Season 6 includes guest stars to have recurring roles:

JACO: A male in his 30s, with an open ethnicity, and a height of 6’4″ or taller, Jaco is described as a silent mercenary who has both brains and brawn, who sounds hyper-intelligent when he speaks.

PAX: A younger male in his 20s, who is a dangerous mercenary like Jaco but has a humorous streak to him.

BUTTERFLY: A female in her 20s, described as unpredictable, aloof, spacey, but nonetheless lethal. Like Jaco and Pax, Butterfly is slated to be a recurring guest star throughout the season.

PROFESSOR L: a brilliant teacher in his 60s who has a positive outlook on humanity but at the same time is disgruntled, bitter, and a mess of a person outside. Professor L will be a recurring guest star as well.

AGENT DAMON: A new SHIELD soldier who is described as being handsome, likable, cool, and funny, but unlike the rest of the characters in this breakdown, and like most SHIELD agents that appear on the show, Agent Damon is only slated to appear for one episode.

As with previous casting calls, all the character names listed are most likely pseudonyms to conceal their identities. However, the descriptions provide some insight on what we may expect.

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The new mercenaries will probably be recurring antagonists, perhaps working for the season's main villain. This central antagonist could be the aforementioned Professor L, a troubled genius with a dark, mean streak.

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After spending much of the fifth season braving time and space, the new characters for Season 6 could hint that the Marvel series is taking things back down to Earth.

Returning in summer 2019 on ABC, Marvel’s Agents of S.H.I.E.L.D. stars Clark Gregg, Ming-Na Wen, Chloe Bennet, Henry Simmons, Ian De Caestecker, Natalia Cordova-Buckley, and Elizabeth Henstridge.

(via That Hashtag Show)