One played Maester Cressen in the hugely successful HBO series Game of Thrones.

The other appeared on screen last year in the fourth season of Netflix historical drama The Crown as Denis Thatcher alongside Gillian Anderson as Margaret Thatcher.

But veteran Olivier Award-winning actor Oliver Ford Davies (Game of Thrones) and Stephen Boxer (The Crown) will be playing novelist Graham Greene and the notorious Soviet spy Kim Philby on stage in Cambridge next week.

A Splinter of Ice opens at the Cambridge Arts Theatre on Tuesday, July 20.

Running until Saturday, July 24, Ben Brown’s coruscating new political drama explores an unlikely friendship.

It is a fascinating historical drama exploring the truth and real friendship between Graham Greene and Kim Philby.

Moscow, 1987. As the Cold War begins to thaw, an extraordinary reunion takes place.

Dunmow Broadcast: Oliver Ford Davies as Graham Greene in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Oliver Ford Davies as Graham Greene in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

As Graham Greene and Kim Philby raise their vodka glasses after 30 years have passed, Brown’s compelling play asks whether Philby betrayed his friend as well as his country, and how much the writer of The Third Man knew about Philby’s secret life.

Playing Graham Greene is Oliver Ford Davies, while Stephen Boxer takes on the role of Kim Philby. Karen Ascoe completes the cast as Rufa, Kim’s Russian wife.

Dunmow Broadcast: Stephen Boxer as Kim Philby in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Stephen Boxer as Kim Philby in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

The real Kim Philby was a British intelligence officer and a double agent for the Soviet Union.

In 1963, he was revealed to be a member of the infamous spy ring, The Cambridge Five, a group that passed information to the Soviet Union during World War II and in the early stages of the Cold War.

Philby attended Cambridge University’s Trinity College, where he studied history and economics, graduating in 1933.

Dunmow Broadcast: Oliver Ford Davies as Graham Greene in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Oliver Ford Davies as Graham Greene in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

Oliver Ford Davies won 'Best Actor' at the 1990 Olivier Awards for his performance in David Hare’s Racing Demon at the National Theatre.

His film and television credits include Christopher Robin, The Last Witness, Star Wars: Episode I - The Phantom Menace, Father Brown, Marple and, of course, Game of Thrones.

Dunmow Broadcast: Oliver Ford Davies, Karen Ascoe, and Stephen Boxer in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Oliver Ford Davies, Karen Ascoe, and Stephen Boxer in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

Boxer’s theatre credits include The Remains of the Day, Titus Andronicus, The Heresy of Love, The Taming Of The Shrew, Bartholomew Fair, Measure for Measure, Twelfth Night, The Herbal Bed, The White Devil, The Duchess Of Malfi, and Richard III, all for the RSC.

His most recent television credits include The Crown, Small Axe, David Elster in Humans, and Poldark.

Evening performances of A Splinter of Ice start at 7.30pm, and there's 2.30pm matinees on the Thursday and Saturday.

There's a BSL interpreted performance on Thursday, July 22 at 7.30pm, and a pre-show talk with Alastair Whatley, artistic director of Original Theatre Company, on Friday, July 23, at 6.30pm.

Dunmow Broadcast: Karen Ascoe in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Karen Ascoe in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

Dunmow Broadcast: Karen Ascoe as Rufa Philby in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Karen Ascoe as Rufa Philby in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

Dunmow Broadcast: Oliver Ford Davies as Graham Greene in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Oliver Ford Davies as Graham Greene in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

Dunmow Broadcast: Oliver Ford Davies and Karen Ascoe in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Oliver Ford Davies and Karen Ascoe in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

Dunmow Broadcast: Oliver Ford Davies, Karen Ascoe, and Stephen Boxer as Kim Philby in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Oliver Ford Davies, Karen Ascoe, and Stephen Boxer as Kim Philby in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

Dunmow Broadcast: Oliver Ford Davies and Karen Ascoe in A Splinter of Ice.Oliver Ford Davies and Karen Ascoe in A Splinter of Ice. (Image: James Findlay)

Dunmow Broadcast: Oliver Ford Davies and Stephen Boxer in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Oliver Ford Davies and Stephen Boxer in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

Dunmow Broadcast: Oliver Ford Davies and Stephen Boxer in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Oliver Ford Davies and Stephen Boxer in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

Dunmow Broadcast: Stephen Boxer as Kim Philby in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Stephen Boxer as Kim Philby in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

Dunmow Broadcast: Oliver Ford Davies and Stephen Boxer in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Oliver Ford Davies and Stephen Boxer in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

Dunmow Broadcast: Stephen Boxer and Karen Ascoe in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Stephen Boxer and Karen Ascoe in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

Dunmow Broadcast: Stephen Boxer and Oliver Ford Davies in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Stephen Boxer and Oliver Ford Davies in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)

Dunmow Broadcast: Stephen Boxer and Oliver Ford Davies in A Splinter of Ice, which can be seen at Cambridge Arts Theatre.Stephen Boxer and Oliver Ford Davies in A Splinter of Ice, which can be seen at Cambridge Arts Theatre. (Image: James Findlay)