Hypercube Hypercubes , also known as tesseracts , were a Time Lord form of communication . Physically resembling white cubes , they were able to store a Time Lord ' s thoughts or speech and could be sent through time and space . They could be used by human s as well as Time Lords . ( PROSE : " Vampire Science " , " The Ancestor Cell " ) They were theoretically impossible to intercept , but a member of Faction Paradox intercepted a cube the Eighth Doctor sent to the Time Lords . They were mainly owned by members of official Gallifrey an organisations . ( PROSE : " Unnatural History " ) History of usages . Irving Braxiatel once used a hypercube to contact his people . ( PROSE : " Tears of the Oracle " ) Stoyn ' s beacon on the sentient planet he was situated on used six white squares , the components of a hypercube . After his beacon was disabled , the Second Doctor pocketed the squares . ( AUDIO : " The Dying Light " ) He was later forced to use them to ask the Time Lords to return the soldiers kidnapped by the War Lord s to their own time periods , as he could not do so on his own . The Doctor constructed his hypercube from the six white squares by merging them with his mind , assembling them into the shape of a cube . Calling upon his people for help proved to be a personal sacrifice for the Doctor , resulting in his separation from his companions Jamie McCrimmon and Zoe Heriot , his exile on Earth , and a forced regeneration into his third incarnation . ( TV : " The War Games " ) The Fifth Doctor used a hypercube to notify the Time Lords that he had found Zero . ( AUDIO : " Spring " ) The Seventh Doctor later slipped Ace a tesseract on the planet Heaven in order to be able to contact her in the future . ( PROSE : " Love and War " ) He later used it to do so whilst arranged for the TARDIS to purge the infection it had contracted after their visit to Tír na n - Óg . ( PROSE : " Deceit " ) During the War , The War King kept the twelve components of a hybercube stacked neatly on his desk as the last remaining link to his past as a renegade . ( PROSE : " The Book of the War " ) During the Last Great Time War , the Eighth Doctor received a hypercube from Susan Foreman . ( PROSE : " Ghost of Christmas Past " ) Susan herself was sent several urgent hypercubes from Gallifrey during the Time War . Most of them were removed by the Eighth Doctor , who didn ' t want her to join the war . ( AUDIO : " All Hands on Deck " ) Cardinal Ollistra sent the Time Lord command to collect her when the Doctor ' s TARDIS crashed . ( AUDIO : " One Life " ) Following the Last Great Time War , a hypercube was on sale at the Fluren Temporal Bazaar . ( COMIC : " Weapons of Past Destruction " ) Hundreds of Time Lords who were stranded in a bubble universe by House attempted to use hypercubes to send distress calls . However , House killed many or all of them for parts to repair Auntie and Uncle , feeding itself on their TARDIS es for five thousand years . One Time Lord to arrive on House was the Doctor ' s good friend the Corsair . He recorded a hypercube , which was sent into the main universe . It eventually found the Doctor ' s TARDIS , because there were no other Time Lords left in time and space . After the Eleventh Doctor arrived in the bubble universe , he heard the distress call s on Nephew ' s translation sphere and thought this meant there were other living Time Lords besides Corsair . The Doctor was enraged when he found a cabinet filled with hypercubes which House had stolen from the dead Time Lords . ( TV : " The Doctor ' s Wife " ) The Doctor kept a hypercube in the TARDIS Drawing Room . ( GAME : " The Gunpowder Plot " ) The New Dalek Paradigm and the Dalek Time Controller sent a hypercube to the Eleventh Doctor ' s TARDIS to lead him to the planet Gethria . From there , the Dalek s manipulated the Doctor into leading them to the Cradle of the Gods , a monument which they planned to use to transform the Sunlight Worlds into copies of Skaro . Aided by Ollus , Sabel and Jenibeth Blakely , the Doctor set the Cradle to self - destruct and the Daleks abandoned the plan . ( PROSE : " The Dalek Generation " ) Behind the scenes . In real - world mathematics , a is an ( n ) dimensional analogue of a cube . A tesseract is a specific hypercube of four dimensions .