Jon Foster will join the USA Network series when it returns in January.

Suits is off for the rest of the year, but it's been busy shoring up actors for its January return.

Accidentally on Purpose star Jon Foster will join the USA Network legal drama in the second episode back as a Mark Zuckerberg type, The Hollywood Reporter has learned exclusively.

Foster will portray "social media wunderkind" Trent Devon, whose company is about to hit Wall Street. When Trent unexpectedly changes his mind, Harvey (Gabriel Macht) discovers his doubts are about more than just the impending IPO.

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Here's the official logline for the episode, "Blood in the Water": "The war with Daniel (David Costabile) may be over, but the battle has left Pearson Hardman vulnerable, and Harvey must protect the firm from a rival whose attack seems as personal as it is professional. Louis (Rick Hoffman) and Mike (Patrick J. Adams) are forced to pay the price for previous actions."

THR previously reported that The Big Bang Theory's Aarti Mann would be appearing when Suits returns as a sought-after law school graduate whom Louis has his eye on. Last week's Suits summer finale hit a season-high 4.5 million viewers.

On the TV side, Foster played Zack on the Jenna Elfman CBS comedy Accidentally on Purpose from 2009-10 and also appeared on NBC's Windfall and ABC's Life as We Know It. He co-starred with his brother Ben Foster in the Woody Harrelson feature Rampart.

Suits will return with new episodes in January.

E-mail: Philiana.Ng@thr.com