she is watching part of a new exhibition at bletchley park where she worked in the war. it was just business as usual. you just carried on? yes. rena was just 21 when she arrived at bletchley. she worked in hut 3, using her degree in german to type up intercepted messages. this was the centre of intelligence where millions of decrypted messages were indexed and analysed. we knew we were reading german messages more or less at the same time as the germans were. and that the people in the field relied on it completely. so, if i press b, you can see m is lit up. there are 103,000 million million million possible ways of encrypting a message with this machine. that's quite a lot, isn't it? that's quite a lot, yes. it's two to the power of 77. breaking the german enigma machine change the course of the war. it's really fundamental to allied success in the war because if you can break enigma you can read such a huge proportion of their traffic and find out about so much of their activity. the new exhibition at bletchley shows just how pivotal intelligence was to the success of

rena stewart is 96, she is watching part of a new exhibition at bletchley park where she worked in theense, really, as far as work was concerned it was just business as usual. you just carried on? yes. rena was just 21 when she arrived at bletchley, she worked in hut 3 using her degree in german to type up intercepted messages. this was the centre of intelligence where millions of decrypted messages were indexed and analysed. we knew we were reading german messages at more or less the same time as the germans were. and that the people in the field relied on it completely. there are 103,000 million million million possible ways of encrypting a message with this machine. that is quite a lot. that is quite a lot, two to the 77. breaking the german enigma machine changed the course of the war. it is really fundamental to allied success in the war because if you can break enigma, you can read such a huge proportion of their traffic and find out about so much of the activity. the new exhibition at bletchley shows just how pivotal intelligence was to the success of d—day. the work here certai

she is watching part of a new exhibition at bletchley park where she worked in the war. cerned, it was just business as usual. you just carried on? yes. rena was just 21 when she arrived at bletchley. she worked in hut three using her degree in german to type up intercepted messages. this was the centre of intelligence where millions of decrypted messages were indexed and analysed. we knew we were reading german messages more or less at the same time as the germans were. and that the people in the field relied on it completely. so, if i press b, you can see m is lit up. there are 103,000 million million million possible ways of encrypting a message with this machine. that's quite a lot, isn't it? that's quite a lot, yes. it's two to the power of 77. breaking the german enigma machine changed the course of the war. it's really fundamental to allied success in the war because if you can break enigma you can read such a huge proportion of their traffic and find out about so much of their activity. the new exhibition at bletchley shows just how pivotal intelligence was to the

gchq began with the heroes of bletchley park, who cracked the enigma code during world war ii. >> h.is so top secret that only friday did officials reveal it old headquarters. a nondescript office block sandwiched between a starbuck's and a pub. top secret no more because gchq recently moved to fancy new digs where the future king got a peek of what they do. >> he wants to get more understanding of how the intelligence services work before he's given the level of briefings he'll be given. >> reporter: the heads of gchq said the prince asked probing questions and showed a real grasp of the missions. and the prince seemed impressed, saying these agencies are people from all walks of life doing extraordinary work to keep people safe. >> david, we appreciate you putting op the trench coat and looking like a spy yourself. >> collar up. >> david wright right there in london with a briefcase that turns into a robot. >>> coming up on "gma," what we're now learning about whether anti-inflammatory drugs can protect against alzheimer's. dr. jen ashton joining us with the results of a new study,

it began with the heroes of bletchley park, who cracked the enigma code during world war ii. is so top secret, only friday did officials reveal its old headquarters, a nondescript office block sandwiched between a starbucks and a pub here in london. top secret no more because gchq recently moved to fancy new digs where the future king got a peek at what they do. >> he wants to get even more understanding of how the intelligence services work before he is given the level of briefings that he will be given. >> reporter: the head of gchq said the prince asked some probing questions and demonstrated a clear grasp of the mission. and the prince seemed impressed saying these agencies are full of people from everyday backgrounds doing extraordinary work to keep people safe. david wright, abc news, london. >> so gchq apparently stands for "golden corral headquarters." did you know that? no, it's "government communications headquarters." they were really impressed with him, said he asked some probing questions that demonstrated a real grasp of the mission. >> the prince for his part s

graham satchell has been to bletchley park.pe. rena stewart is 96. she is watching part of a new exhibition at bletchley park where she worked in the war. what was the atmosphere like here at bletchley as d—day approached? well, it was very tense, really. but as far as work was concerned, it was just business as usual. you just carried on? yes. rena was just 21 when she arrived at bletchley. she worked in hut 3, using her degree in german to type up intercepted messages. this was the centre of intelligence where millions of decrypted messages were indexed and analysed. we knew we were reading german messages more or less at the same time as the germans were. and that the people in the field relied on it completely. so, if i press b, you can see m is lit up. there are 103,000 million million million possible ways of encrypting a message with this machine. that's quite a lot, isn't it? that's quite a lot, yes. it's two to the power of 77. breaking the german enigma machine change the course of the war. it's really fundamental to