Following a surprise nomination on Sunday, Latoya and Emilia have been announced as the next two housemates to face eviction by public vote.Yesterday also saw the house being hijacked by actor Mackenzie Crook who announced that; “Today is Nerd Day.The star of The Office informed the housemates that, since he was best known for playing "the ultimate twisted nerd" on the hit BBC sitcom, their task would be to transform into nerds.John relayed further details about the challenge, informing each housemate of their specific nerdy qualities. Anthony and Calista were told they would spend their time building military models and ships. John, Amy and Nathan were subjected to medieval fantasy role-playing and were given costumes to help them to act out a story for show and tell.Jay, Emilia and Latoya were given the joyous task of being bird watchers for the day and at Big Brother’s discretion, birds will fly into the garden. Jeremy had the task of building the world’s biggest rubber band ball and was given a ping pong ball as a base to get him started.The housemates were quick and eager to adopt their nerdy personas as costumes specific to each of the housemates' particular nerdy hobbies were provided in the store room, and soon the transformations began to take shape.Jeremy was given a Trekkie outfit complete with Spock ears. The bird-watching trio were dressed into shorts, wellington boots, bobble hats, thick spectacles and bad false teeth. Fantasy role-players Nathan, Amy and John got kitted out in helmets, tunics and fake swords and shields.

Model-maker Anthony was similarly thrilled, enthusing: "I think these are pretty cool. My tweed jacket, I look like Ross from Friends.

However, his hobby partner Calista was less keen - jazzing up her dowdy over-sized jumper with a hat, she was reprimanded by Crook who insisted that it wasn't nerdy enough.

The bird watchers then had to go and sit outside in the pouring rain with see-through umbrellas and waited for birds to come into the Big Brother garden. When the first bird flew over the garden fence Latoya announced: "It looks like a penguin! I'll draw it. Oh my God, it's flying away." They all retreated into the house to draw the bird in their spotter jotters, when Mackenzie advised them that they should all get back in the garden so they could spot the other birds.

John, Amy and Nathan were considerably drier as they rehearsed a battle scene for their show and tell. Amy and Nathan played Lord Hindof and Sir Dropsalot, who wanted to pass through the city of Dark Lord Sir Gorier, played by John.

When it came to show and tell later in the evening, model-makers Calista and Anthony demonstrated their handiwork - the Tornado GR4/GR4A. After the other groups had shown their achievements, the final nerd to the stage was Jeremy, who keenly elaborated on his "favourite hobby - rubber balling".

Dressed in a Star Trek costume, the racing car driver commented on the merits of rubber-balling, saying: "I find it therapeutic... It almost becomes a pet. It also acts as a clever rubber band storage device and as a bouncy ball. It can also be used at home as a bicep curl weight or in game of catch with friends."

Mackenzie Crook seemed impressed with the nerdiness of all the housemates, but opted for the Trekker to be the overall winner as he managed to talk so enthusiastically about his hobby. Jeremy earned a model train for his efforts, as Latoya congratulated the racing car driver for his "top nerdage".

Later that evening, Jeremy continued to tell his fellow housemates of his theory that John is a mole. Having shared his suspicions with Emilia and Amy the day before, Jeremy then discussed the matter with Nathan and Jay.

Nathan was initially very much in agreement, saying: "Even if he's a not a mole, there is something going on with him." Amy suggested that the likelihood of the Scotsman having a secret agenda was "99% false and 1% possible," though Emilia was more convinced. "I'd give it like 40%," she corrected.

FemaleFirst Ruth Harrison

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