A brilliant, difficult mathematician built a machine to crack Hitler's "unbreakable" code — and his own country later destroyed him for who he loved.
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Work through the four short activities. Each word is shown in a situation that gives its meaning away — no need to know the film yet. Say your answer out loud first, then reveal.
Morten Tyldum's The Imitation Game (2014). Read each part, try the quick check from memory, then discuss. (There are spoilers ahead — that's the point; we're here to talk about it.)
It is 1939, and Britain is at war. At Bletchley Park, a country estate turned top-secret code-breaking centre, the brilliant but painfully awkward mathematician Alan Turing arrives to join the fight against Enigma — the machine Germany uses to scramble every military order into a code that changes at midnight, every night, into one of an almost unimaginable number of possible settings. Turing is blunt, literal-minded and hopeless with people; he clashes almost immediately with his commander, Denniston, and with the more socially adept codebreaker Hugh Alexander, who leads the existing team.
Turing's idea horrifies everyone: a human mind can never beat Enigma quickly enough, he argues, so the only answer is to build a machine that can. When Denniston refuses to fund anything so strange, Turing writes directly to the Prime Minister and gets the money regardless — earning him few friends. He also insists on recruiting Joan Clarke, a gifted young mathematician the interview board almost turns away for being a woman, and quietly arranges for her parents to be told she is doing respectable clerical work rather than confidential codebreaking.
Turing pours everything into an enormous, clattering machine of dials and wires. For a long time, it does not work at all.
1. Why is Enigma so difficult to break, and what does Turing insist is the only way to beat it?
2. What does Turing do to get his machine built, and who does he insist on recruiting?
1. Enigma changes its settings every single day, giving it an astronomical number of possible combinations — far too many for people to check by hand — so Turing insists only another machine can beat a machine.
2. He goes over his commander's head and writes to the Prime Minister for funding, and insists on recruiting Joan Clarke, a talented mathematician the board initially rejects for being a woman.
Turing's machine strips through possible settings, but with millions of combinations still to test each day, it is hopelessly slow — until, in an ordinary pub conversation, Joan Clarke points out that German radio operators are creatures of habit: certain words appear in messages so reliably that they can be used as a shortcut, a known fragment to search for instead of testing everything from nothing. Fed this "crib," the machine finds a day's settings in minutes instead of years. In one tense night, Enigma falls.
The celebration is short-lived. Turing and his colleagues realise, almost as soon as the champagne appears, that using everything they now know will hand Germany the one clue that would ruin them: if every convoy is suddenly saved and every attack somehow anticipated, the enemy will simply change the code again, and years of work will be wasted. So a small, sworn-to-secrecy group, reporting to an intelligence officer, must decide, message by message, which disasters to quietly prevent and which to let happen, calculating losses like a grim sum, to protect the secret that the code is broken at all. In the film's bleakest scene, that arithmetic costs the team a colleague's own brother, serving on a convoy they choose not to save.
1. What breakthrough finally lets the machine crack Enigma's daily settings?
2. Why can't the team act on every piece of intelligence the broken code now gives them?
1. Joan Clarke notices that German operators repeat certain predictable words, giving the team a "crib" — a known fragment of text the machine can search for, instead of testing every possibility from scratch.
2. If they save everyone and stop every attack, Germany will realise Enigma has been broken and change the whole system, so a small group must let some disasters happen to keep the secret and protect the far larger advantage.
The war ends, and the codebreakers are ordered to destroy their machines and every paper record, and to swear permanent secrecy about work that has just helped win a world war. They scatter to ordinary lives, unable to tell anyone — family, friends, future employers — what they actually did.
Some years later, in 1951, a burglary at Turing's home brings a police detective into his life; digging further than the burglary requires, the detective uncovers Turing's relationship with another man. Under the law of the time, this is a crime, and Turing is arrested and prosecuted for it. Offered a choice between prison and a period of enforced hormone treatment, he chooses the treatment, and its effects — on his body and his mind — are visibly devastating.
A closing title tells us what happened next: Turing's conviction stood, his part in winning the war stayed classified for decades, and it was only in 2013 — years after his death — that Britain finally issued him an official pardon.
1. What are the codebreakers ordered to do once the war ends, and what does that cost them personally?
2. What happens to Turing in the early 1950s, and what choice is he given?
1. They must destroy their machines and papers and swear lifelong secrecy, meaning they can never tell anyone — even close family — what they really did during the war.
2. A police investigation uncovers his relationship with a man, a crime at the time; he is prosecuted and, to avoid prison, chooses a period of enforced hormone treatment instead.
This is a story about who deserves the credit, and what the record leaves out — exactly the kind of story English's emphasis structures were built for. A cleft sentence splits one plain idea into two parts so you can throw the spotlight onto precisely the piece of information that matters most.
Complete each sentence with an it-cleft. Use It was/is + the emphasised words (given in brackets) + who or that.
1. designed the British Bombe, although the idea grew out of work already done abroad. (emphasise: Turing)
2. shared their code-breaking methods with Britain, just weeks before the war began. (emphasise: the Polish mathematicians)
3. the codebreakers were ordered to stay silent for the rest of their lives. (emphasise: at Bletchley Park)
1. It was Turing who (it-cleft, emphasising the person)
2. It was the Polish mathematicians who (it-cleft, emphasising the people)
3. It was at Bletchley Park that (it-cleft, emphasising the place)
Complete each sentence with a what-cleft. Use What + the rest of the idea + was.
1. was a way to test thousands of settings automatically, far faster than any human. (emphasise: what the team needed)
2. was how much of the breakthrough depended on a whole team, not one man alone. (emphasise: what surprised historians later)
3. was permanent silence — most could never tell even their own families. (emphasise: what the secrecy oath demanded of them)
1. What the team needed (what-cleft)
2. What surprised historians later (what-cleft)
3. What the secrecy oath demanded of them (what-cleft)
Fill each gap with a cleft sentence or an emphatic do/does/did, whichever the meaning needs.
Popular memory often credits one lone genius with beating Enigma. In fact, laid the crucial groundwork years earlier, cracking the machine's wiring long before Turing ever reached Bletchley Park. was patience: tens of thousands of messages, tested one gruelling day at a time by a team of thousands. And although history almost forgot them, the Polish team eventually receive recognition — just decades later than they deserved.
it was Poland that / it was the Polish mathematicians who · What the work needed · did
Notice the pattern: it-clefts single out one fact people got wrong; what-clefts save the key idea for last; emphatic did insists against a doubt.
Carry these into the Speak tab — this whole story is an argument about who really deserves the credit, and cleft sentences are exactly how you make that argument in English.
The Imitation Game is unusual among films like it: the true story underneath is arguably more important than the film itself, and the film gets the broad shape right while inventing or simplifying a surprising amount of the detail.
Alan Turing (1912–1954) was a British mathematician and logician now regarded as one of the founding figures of computer science. His 1936 concept of a theoretical "universal machine" — a device that could, in principle, carry out any computation — underlies how every modern computer works. The standard test for whether a machine can convincingly imitate human intelligence still carries his name: the Turing Test.
Enigma was the cipher machine Nazi Germany used to encrypt military communications; its settings changed daily, producing an astronomical number of possible configurations. What the film doesn't mention is that Enigma had already been broken once before: in the early 1930s, Polish mathematicians — chiefly Marian Rejewski, working with colleagues Jerzy Różycki and Henryk Zygalski — worked out the machine's internal wiring and built their own code-breaking machine, the "bomba." In July 1939, weeks before Germany invaded Poland, they shared their methods and a reconstructed Enigma with British and French intelligence — the head start that made everything at Bletchley Park possible.
At Bletchley, Turing — working closely with fellow mathematician Gordon Welchman and others — designed the British Bombe, an electromechanical machine that tested Enigma settings far faster than any human could. The first was installed in 1940. Bletchley Park's workforce grew to roughly 10,000 people by the war's end, most of them women; Turing worked in Hut 8 alongside cryptanalyst Joan Clarke — his real colleague, and briefly his fiancée — plus figures such as Hugh Alexander and Peter Twinn. Historians estimate that breaking Enigma and related German codes shortened the Second World War by roughly two to four years, saving an enormous number of lives.
The machine was never really called "Christopher." The film's detail — that Turing named it after a childhood friend who died young — is an invention for emotional effect; the real Bombes were given other designations. More importantly, Turing was not a lone, friendless genius who single-handedly built the machine: it was a collaborative achievement, designed with Gordon Welchman among others, and built directly on the prior Polish breakthrough — the work of a team of thousands, not one man's solitary triumph.
The film's spy subplot is also largely invented. John Cairncross really did pass secrets from Bletchley Park to the Soviet Union, but he worked in a different section, and historians (including Turing's biographer Andrew Hodges) find no evidence that he and Turing ever met, let alone that they blackmailed one another as the film shows.
The persecution, however, is real, and the film is largely faithful to it. In 1952, Turing was prosecuted for a relationship with a man — a crime in Britain at the time — and chose chemical castration (hormone treatment) over prison; he lost the security clearance that had defined his working life. He was found dead in June 1954, poisoned by cyanide; a coroner ruled it suicide. Britain issued him a posthumous royal pardon in 2013, followed in 2017 by "Turing's Law," which pardoned thousands of other men convicted under that same historic law.
This is the heart of the lesson — do it all out loud. The timer keeps you going; fill the time with detail.
Tell the story of The Imitation Game in your own words, as if to someone who has never seen it. Move through the arc: the impossible machine at Bletchley Park → the crib that finally breaks Enigma → the terrible choice about which disasters to prevent → the postwar secrecy → the persecution that followed years later.
Work in at least five key words (meticulous, painstaking, breakthrough, clandestine, unravel, ostracise, prosecute, pardon, ingenious, ponder), and use at least one cleft sentence for emphasis: "It was Turing who…"
The team decides not to save people they could save, message by message, in order to protect a bigger secret. Build an argument: can withholding help that would cost lives ever be justified by a larger goal — or is deliberately allowing harm, even for a good reason, never acceptable? Bring in other examples you know — whistle-blowers, doctors, intelligence services, undercover work.
Turing's genius helped save lives, but his own country prosecuted him a few years later for who he loved. Talk about a case — from history, current events, or your own experience — where someone was judged unfairly for something that shouldn't have mattered.
Stuck for an idea? Pick one of these and run with it: