Klein has been cast as an old-school friend of Mark-Paul Gosselaar's Peter Bash, reports Entertainment Weekly.
His character has been described as a "charismatic politician" who has a family scandal that they want to keep secret.
Law & Order's Paul Schulze will also star in the episode as Klein's campaign manager, who doesn't get on well with Bash or Jared Franklin (Breckin Meyer).
Other guest stars previously confirmed for the show's second run include Cybill Shepherd, Sean Astin, Rick Fox, Jane Seymour, Seth Green and Beau Bridges.
The second series of Franklin & Bash is expected to air on TNT in the summer. E4 aired the first series in the UK last autumn.
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