Television Joe Armstrong's first television role was a bit part in a 2003 episode of
The Bill, followed by a brief appearance in the ITV mini-series
Between the Sheets starring his father
Alun Armstrong. In the 2004 BBC film
Passer By, he had a supporting role as one of two men accused of assaulting a woman on a train. He guest starred in the 2004
Waking the Dead episode "Fugue States" as a young man who reappears with amnesia after being abducted as a child. Also in 2004, he played the son of a murdered farmer in the ''
Foyle's War'' episode "They Fought in the Fields." Other television credits include guest spots in
Midsomer Murders (2004),
Blackpool (2004),
Rose and Maloney (2005), another episode of
The Bill (2005),
The Inspector Lynley Mysteries (2006),
Party Animals (2007),
The Last Detective (2007) and
The Whistleblowers (2007). In 2006, Armstrong was cast in the BBC series
Robin Hood as
Allan—based on the legendary figure
Alan-a-Dale—who joins
Robin's band of outlaws in
Sherwood Forest. Allan later becomes allied with the sympathetic villain
Guy of Gisborne but has a change of heart and rejoins his friends. Armstrong appeared in all three series from 2006 to 2009. The series was filmed on location in and around
Budapest. Armstrong portrayed
Norman Heatley in the 2009 BBC Four film
Breaking the Mould about the team who turned penicillin into a viable medicine. In 2010, he co-starred with
Billie Piper in the two-part drama
A Passionate Woman as the husband of a woman who has an affair. His father Alun Armstrong played the older version of his character. He appeared in
Public Enemies starring
Daniel Mays and
Anna Friel in 2012. Armstrong played
Hotspur in
Richard Eyre's 2012 production of
Henry IV, Part I—one of four films in the BBC Two Shakespeare cycle
The Hollow Crown. He employed a
Geordie accent for the role.
Jeremy Irons played
Henry IV, with
Tom Hiddleston as
Prince Hal and Alun Armstrong as Hotspur's father, the
Earl of Northumberland. In the 2013 drama
The Village, depicting life in a
Derbyshire village in the early 20th century, he played Stephen Bairstow, a detective scarred by his experiences at the Front in
World War I. The character was originally a minor one, but writer
Peter Moffat expanded the role because he was impressed with Armstrong. He reprised his role in the second series in 2014. Armstrong played drug dealer-turned-kidnapper Ashley Cowgill in
Sally Wainwright's 2014 crime drama
Happy Valley, starring
Sarah Lancashire. In December 2016 he also appeared as William Allison in Wainwright's
To Walk Invisible, a television biopic about the lives of the
Bronte family. In 2016, he appeared in "
Hated in the Nation", an episode of the
anthology series Black Mirror. In 2018, he appeared as series regular Gildas in
Britannia,
Jez Butterworth's historical drama about the
Roman conquest of Britain. The following year he played Samuel Washington in the BBC/HBO co-production
Gentleman Jack, written by Sally Wainwright. In 2024, Armstrong appeared in the Harlan Coben Netflix adaptation of 'Fool Me Once' as Alexander Dosman, ex-boyfriend of Claire Walker and father to their son Louis.
Theatre Performing with the
National Youth Theatre, Armstrong's roles included Gerry Evans in
Dancing at Lughnasa in 1998 and Lieutenant Stedna in ''They Shoot Horses, Don't They?
in 2000. He also played Wackford Squeers in Nicholas Nickleby. He appeared in How Love Is Spelt by Chloe Moss at the Bush Theatre in 2004 and in A Night at the Dogs'' by
Matt Charman at the Soho Theatre in 2005. At the
Edinburgh Festival Fringe in 2009, he played Liam in the
Dennis Kelly play
Orphans. The play premiered at the
Traverse Theatre in August and then moved to the
Birmingham Repertory Theatre in September and the
Soho Theatre in London in October. Armstrong was nominated for a
Stage Award for Best Actor. In the
DC Moore play
The Empire, Armstrong starred as Gary, a Lance Corporal in Afghanistan guarding an injured prisoner who claims to be British. Paul Taylor of
The Independent wrote: "Gary ... veers between seething anger and low-key sarcasm, an oscillation superbly conveyed by excellent Joe Armstrong." In preparation for the role, Armstrong and other cast members met with soldiers who had served in
Afghanistan. The play had a six-week run at the Jerwood Theatre Upstairs in the
Royal Court Theatre from March to May 2010 followed by two weeks at the Drum Theatre in the
Theatre Royal, Plymouth in May. Armstrong played RAF tail gunner Dusty Miller in
Terence Rattigan's World War II drama
Flare Path in 2011. The critically acclaimed revival directed by
Trevor Nunn ran from March to June at the
Theatre Royal Haymarket. In 2012, he played Jean in
Miss Julie opposite
Maxine Peake in the title role at the
Royal Exchange Theatre in
Manchester. Armstrong described the role as one of his most challenging because of the need to make his character's sudden changes in mood believable. Alfred Hickling of
The Guardian remarked that "Joe Armstrong's Jean ... flips back and forth between brute arrogance and fawning servility with the casual manner of tossing a coin." In a 2013 production of
Harold Pinter's
The Dumb Waiter at
The Print Room, Armstrong played Gus alongside
Clive Wood as Ben. Matt Trueman of
The Telegraph called Wood and Armstrong "two perfect Pinterians," and Fiona Mountford of
The Evening Standard wrote, "Armstrong, always an actor of easy geniality, flourishes in particular with this short, sharp, light-footed humour." Armstrong co-starred with
Louise Brealey in the 2015 touring production of
Constellations.
Film In 2006, Armstrong was in two short films:
A Ticket Too Far and
Service. The latter was part of the
Coming Up series on
Channel 4. He appears in
Nae Caranfil's film
Closer to the Moon, also starring
Vera Farmiga,
Mark Strong and
Harry Lloyd, which was filmed in
Bucharest in the autumn of 2011 and was released in Romania in 2014. The film is about the bank robbery allegedly committed by the
Ioanid Gang in 1959 Romania. Armstrong's character Răzvan is based on the journalist Haralambie Obedeanu who was one of the accused. In 2017 Armstrong appeared in
Joe Wright's war drama
Darkest Hour, his major studio debut.
Radio Armstrong performed in the BBC radio plays
Girl from Mars in 2008 and
Hitched in 2010, and he read the story
Gifts by
Garry Kilworth as part of a Christmas radio programme. In 2011, he co-starred with
Richard Briers and
Edna Doré in the Radio 4 drama
A Shoebox of Snow. Armstrong reprised his role in DC Moore's
The Empire for a BBC Radio 3 production. He was in the radio serial
Ruthless by Tim Loane on Radio 4 in 2012. In 2013, he played Sergei in a Radio 4 adaptation of
Lady Macbeth of Mtsensk, and he appeared in the series
The Corrupted by
G. F. Newman. He performed in the drama
Ghosts of Heathrow in 2014 and in adaptations of
The Bone Clocks,
The Book Of Strange New Things and
The Trial. ==Screen and stage credits==