Here's Hulu's description of the upcoming seven-episode arc:
Government embarrassment, ministerial cock-up, coalition rows, backroom deals, policy U-turns, spin doctoring, political back-stabbing, wild media speculation, and more time spent with one's family. It can only be the eagerly-anticipated return of Armando Iannucci's sharp political satire "The Thick of It". Rebecca Front and Peter Capaldi reprise their BAFTA-winning roles as Nicola Murray and Malcolm Tucker, now consigned to the opposition benches, but still desperate for power. Roger Allam returns as Peter Mannion, the new Secretary of State for Social Affairs, supported by his team of special advisors and thwarted by his new coalition partners.
Hulu has the first three seasons of "The Thick of It" up (and unbleeped!) online here. Check out a clip from the first episode of season four below: