Tom Stoppard's plays are renowned for compelling audiences to learn forward and listen as big ideas are interlaced with human relationships.

Nina Raine's revival of his drama, set between Cambridge and Czechoslovakia, from the Prague spring of 1968 to the velvet revolution of 1989, is more a game of two halves.

As grizzled Marxist lecturer Max (Nathanial Parker) argues with his rock n roll loving Czech PHD student Jan (Jacob Fortune-Lloyd) it assumes a working knowledge of Cold War politics and Soviet history that feels like homework.

Ham & High: Jacob Fortune-Lloyd and Nancy Carroll in Rock N RollJacob Fortune-Lloyd and Nancy Carroll in Rock N Roll (Image: Manuel Harlan)

Max continues to espouse Communist ideals from the comfort of his Arts and Crafts Cambridge home, while Jan returns to Prague, where his counter-cultural vinyl collection draws him unwillingly into activism - and the repressive surveillance of the state.

All the seeds of the second half are sown in the first; a strange pan-like musician who relates to Pink Floyd co-founder Syd Barrett; dense dissections of Sappho's sensual poetry; arguments about freedom, and whether Stalin was as bad as Hitler.

But so much of it is tell-not-show that it makes you wonder if this intellectual wordplay overstuffed with ideas reads better on the page.

Ham & High: Nathaniel Parker and Colin Tierney in Rock N RollNathaniel Parker and Colin Tierney in Rock N Roll (Image: Manuel Harlan)

Luckily in the second half everyone starts behaving more like passionate humans than mouthpieces for ideas, Stoppard can certainly turn a zingy phrase, and a beautiful, unexpected love story emerges, along with engaging ideas about Britain's own revolutionary timidity, and the illusion of liberty.

Played in traverse, the impact of some performances get lost, and while Raine punctuates scene changes with the cast grooving to Rock 'n' Roll tracks by The Velvet Underground, Pink Floyd and Beach Boys, its more dad dance than feral rave.Ham & High: Nancy Carroll in Rock N RollNancy Carroll in Rock N Roll (Image: Manuel Harlan)

Nancy Carroll raises the emotional temperature as both Max's impassioned cancer-stricken wife Eleanor, and wild child daughter Esme.

Parker has a rather thankless task as a deluded Commie whose ideals have cost him little, but Fortune-Lloyd pulls back a timid start with an uplifting final scene as the middle-aged Jan, finally able to dance freely on a table to The Rolling Stones.

Rock N Roll runs at Hampstead Theatre until January 27.