Adam Mitchell

Adam Mitchell is a character in Doctor Who, who appeared in the revival's first series for two episodes as a short-term companion to the Ninth Doctor, and was banished from the TARDIS. The character was portrayed by Bruno Langley.

Adam Mitchell wasn't seen in the series again, but did return in the 2013 comic book series Prisoners of Time as one of the primary antagonists in which he plans revenge against all the Doctor's incarnations for his banishment.

Biography
Adam first appears as a young researcher working for Henry van Statten, who is the owner of a museum of extraterrestrial artefacts. He forms an attraction for the Ninth Doctor's companion Rose Tyler and reveals his love to see the stars. He ends up fleeing with Rose when a live Dalek kept within the base ends up on the loose. After the creature's death and the museum closes down, Rose convinces the reluctant Doctor to allow Adam to come along with him, which he eventually accepts.

However the travels with the Doctor doesn't last long. When they end up in the year 20,000 on a Space Station, Adam becomes tempted with the wealth of futuristic information. He has an advanced computer interface port installed inside his head, which can be activated with the click of someone's fingers which opens up his head. He attempts to send back information to the 21st Century using Rose's modified mobile phone, but this act allows the villains on the station to extract information on the Doctor from Adam's brain. As punishment, The Doctor later banishes Adam back to the 21st Century and destroys his answering machine to eliminate the future information. He advises Adam to live a quiet life, and departs in the TARDIS with Rose. When Adam's mum returns home, she reacts in shock after she ends up snapping her fingers and her head opens up.