Mike starts his new job as an investment banker and Harvey has to cope with losing his right hand man tomorrow night on the Suits season 4 premiere, “One-Two-Three-Go…”

After seasons of tense hand-wringing fear, and an extremely close call during the season 3 finale, Mike Ross has left the world of legal practice he illegally entered and is now embarking on a new pursuit: investment banking. Brought on by his former client, Johnathan Sidwell, in the season 3 finale, Mike has a chance to reinvent himself in this new atmosphere. Again.

The decision to leave was not taken lightly. Mike consulted those he trusts most, and while Rachel said he should go and Harvey said it in so many words, he was determined to stay at Pearson Specter. Until he jeopardized the freedom and friendship of Harvey, Louis and Harold in the March season 3 finale.

So what does Mike have in store for himself at the investment bank? A new office, new coworkers, and the small fact that powerful Harvey Spector now works for him. That shouldn’t be a problem.

There’s also lots of guest stars set to appear in many of the 16-episode season. The first bulk of 10 episodes begins tomorrow night and airs through the summer, and the final six can be expected in early 2015, as per USA Network’s M.O.

Watch a sneak peek of tomorrow night’s ‘Suits’ season 4 premiere:

‘Suits’ season 4 casting news:

The following men have been announced as guest stars, and in some cases, reoccurring roles, for this upcoming season.

Neal McDonough: Tapped to play ‘bulldog’ Sean Cahill, an SEC investigator who is Pearson Specter’s next thorn in their side, Sean Cahill works for Eric Woodall (Željko Ivanek, who appeared in the season 3 finale interrogating Mike and Harold) in attempts to discover any wrongdoing in the firm.

Eric Roberts: According to Access Hollywood, Charles Frontman sounds like many of the other Suits characters that have come and gone in seasons pasts. Described as a titan of finance, Charles has a net worth in the billions and a big personality.

Michael Gross: The former Family Ties star will appear in Suits as Walter Gillis, a “down-to-earth founder of a DVD distribution company” who goes to the law firm for help to protect his business.

The official description for the ‘Suits’ season 4 premiere:

“Mike and Harvey adjust to their new paradigm. As they butt heads over strategy in Mike’s first foray into investment banking, their new attorney-client relationship may be short-lived. Meanwhile, Pearson Specter discovers that a disgraced former District Attorney may be pursuing a vendetta against Harvey and the firm.”

‘Suits’ season 4 premieres June 11 at 9 pm.