He was portrayed by Bill Nighy in the live action adaptation of Stormbreaker. In the Amazon Prime series, he is portrayed by Stephen Dillane.
Alan Blunt was first in the Army, and at university, he went to the same university as Michael Roscoe, a billionaire in New York who was later killed by the Gentleman. Alan Blunt was keen in mathematics, and he excelled in mathematics and business, becoming involved in intelligence work. Despite being loyal to his country, however, he hated the prime ministers - considering them untrustworthy and unreliable and because they hated MI5 and MI6.
One day, Alan Blunt suggested recruiting a child, for intelligence work, but the prime minister (Tony Blair) said that it was insane. However, Blunt had already disagreed.
Blunt was not long head of MI6 before a new organization came to the world's attention, which was SCORPIA, the Sabotage, Corruption, Intelligence and Assassination, (from the initials the name was made) which was formed by retired spies who wanted more money. Blunt knew of the leaders but was unable to stop them.
Alan Blunt was friends with his deputy Tulip Jones and he was around when her children were kidnapped and her husband killed. But Alan Blunt promoted Tulip Jones and he put her into the field. He gave her her first assignment when SCORPIA kidnapped Graham Adair's son, Graham was a friend of Blunt's and he owed him. So they arranged a loan with SCORPIA, that MI6 would have the son and SCORPIA would have the money. Tulip Jones was stationed on Albert Bridge in London by Westminster and the crossover was dealt with, but it went wrong because Julia Rothman was in charge of the SCORPIA branch and she was in love with John Rider, the agent in charge of the MI6 branch and when she felt betrayed by him, she ordered his assassination, so Rider faked his death.
One of Blunt's most evil acts was his corruption of Ash, because through Blunt's neglect and presumption that Ash would never betray him, Blunt made Ash hate MI6 and Britain and he ended up in the enemy hands anyway. Blunt never knew of this or suspected it and he saw Ash as useless and cannon fodder, and Alan Blunt corrupted Ash into evil.
Alex Rider was Ian Rider's nephew and John Rider's son and Alan first met him at the funeral of Ian Rider, where his allegiance to MI6 was first revealed (although Blunt said he was with a banking company, the Royal and General). Alex was first drawn in when he saw a gun under an agent's jacket at the funeral.
Alex was later recruited by Alan Blunt who cruelly made a near-perilous experience for Alex by making him jump fourteen floors up to a flag outside, then out into Ian's office, where he learned the secrets of his intelligence work. Alex later joined MI6 himself, or rather, he was bullied into joining by Blunt, who blackmailed him pure and simple by saying if he refused to join, his housekeeper Jack Starbright would be deported back to America, and Alex would be placed in a foster home in North London. Blunt outright said he controlled Alex's future, and he sent him to Army training without a thought for his injuries.
During the training, Blunt said that it would help him if Alex was killed by Herod Sayle, because then it would prove something was wrong. But Alex survived the entire operation. Sayle was killed and Alex thought Blunt would at least pay him for risking his life, but all he got was congratulations.
When Alex was arrested for damaging a police center (actually he was trying to arrest drug dealers), Blunt threatened to return him to police if he didn't volunteer for his next assignment. So Blunt sent him to Point Blanc academy, and when the evil headmaster Dr. Hugo Grief almost eviscerated Alex alive, Blunt refused to help because of political issues with the French. He just said "This is the French we're talking about and you know what they're like."
Alan Blunt then sent Alex into the "front line of World War Three" by sending him to Cuba where he met General Alexei Sarov, an evil madman with a bomb, and Alex survived, only just. He was mentally scarred.
Alan Blunt then refused to listen to Alex when Alex said Sir Damian Cray was involved in terrorism, and Alan kicked out Alex onto the street after watching Sabina dump him. When Sabina was kidnapped by Sir Damian, this got Blunt's attention, and finally he called authorities, almost too late from the destruction of South America and Africa, and got a dressing down confrontation with the home secretary and prime minister and was threatened with early resignation.
Next, Alan Blunt heard Alex had met SCORPIA themselves and was embroiled in their training. He was prepared for the worst, so when SCORPIA introduced their next weapon, nanoshells in ray guns to kill humans, Alan Blunt knew what to do. He arrested Alex when Alex almost murdered Tulip Jones (in supposed revenge for her allegedly killing his father) and interrogated him and finally recruited Alex again for stopping SCORPIA.
Blunt was not involved in the American mission with the Ark Angel space hotel, he was investigating the terrorist board Force Three and too busy with them for Alex.
Alan Blunt was next seen in the events of Crocodile Tears where he played a more prominent role. Blunt was arguing with the prime minister (now Gordon Brown) and he was angry with his suggestion to first not take Alex seriously and also to bomb the poisoned wheat field.
Fortunately, the field needn't be bombed, for Alex flooded it and drowned the contamination before it spread.
Alan sent a sniper to Alex's school to convince Alex to go to Egypt to save his friends from danger and put Alex's friend's life in danger and threatened the entire school. Alan was unconcerned when Jack was murdered, saying she was just a "housekeeper" and a necessary death. Alan was given a dressing down by Tulip Jones, who threatened to make his atrocities known publicly, saying he organized a shooting in an English school. But Tulip did nothing, knowing that Blunt was near a knighthood. She let him off, and Blunt just said sometimes fighting monsters makes one into a monster. Then he went to his knighthood and went to Venice for a holiday.