- "If you started making out with me it would look like you were grinding the invisible man."
- ―To Christa
Adam Jacobs is an eternally teenage vampire who befriends George and Nina when he's feeding at the hospital his father is hospitalised in. He went on to form his own supernatural trinity and eventually married a succubus in late 2012.
Adam was born in 1964. When he was 16 in 1980, he fought an unknown vampire that ended in him being turned into a vampire. His parents kept him fed for years until his mother died and his father ended up in hospital.
He first meets George and Nina when he was found by the latter drinking from his father. After explaining his situation, Nina allows him to stay with her and George much to the disapproval of Mitchell, who believes the presence of another vampire might be bad for him.
Eventually he is taken in by a vampire couple (Emma and Richard) with a swinger lifestyle which he finds appalling and decides to go back with George and Nina. Mitchell gives him some money to start over somewhere, Adam concluding that he had to move on and find his own life in order to stop himself being a burden on George and Nina like he was on his parents after they decided they would be willing to become surrogate parents to him to keep him safe.
He eventually finds himself back in school, with the goal of getting some qualifications, where he befriends a werewolf named Christa and a ghost named Matt. During this time, Adam worked with Matt and Christa to investigate Matt's murder -despite the current tension developing between them due to Matt's feelings for Christa and Christa and Adam developing some degree of feelings for each other, also contacting George for advice on how to handle Christa's condition.
The murderer was subsequently revealed to be Matt's old teacher, Mr Roe, who had become enraged at the irreverent way he was treated by his students, Adam almost attacking him before Christa talked him down. Roe was subsequently thrown through Matt's door when he tried to attack Adam and Christa to protect his secret. Despite winning, Adam points out that they may have caused problems by sending Roe through Matt's door.
Adam returns to Honolulu Heights in 2012, having left Christa and Matt. He is on the run from the press, who have found out that he is in a relationship with Yvonne, the Headmistress of a girls' school. Once at the house he explains to her that he is a vampire, but at that point Hal discovers that Yvonne is a succubus - a creature who subconsciously causes men to fall in love with her whenever they touch her.
Adam is taken out of the house by Annie, and he is horrified at what he has done. However, he eventually realizes that he does love Yvonne, and returns to the house to fall under her spell once more. The two of them leave the next day, to continue their lives together.
According to Rook's emails, Adam and Yvonne got married in Gretna Green in late 2012. It appears that Adam has gone completely dry of blood since. However, in the email Rook mentions that Adam was being tracked by the DoDD during the later part of 2011 using the trail of half drained women, suggesting that he had almost fully embraced his blood lust between Becoming Human and Series 4. In 2012 the Department of Domestic Defence finds out that he and Yvonne are on their way to Northern Scotland. The Department of Domestic Defence also knows that Adam's friend Christa Stammers is living there on the Isle of Grimsay. His current status following the Devil's victory is unknown however.
Adam possesses all the standard powers and weaknesses of a typical Vampire; including enhanced strength and resilience, greater than any human, invulnerability to most conventional causes of harm and fatality, enhanced senses, awareness of the supernatural, retractable fangs, immortality, advanced healing, his image cannot be captured on camera or in a photo and the ability to ingest and digest blood. However, Adam's young body leaves him at a disadvantage against more physically mature vampires.
Adam is known by his flirtatious, rude and sometimes perverted attitude to people. This causes people to often dislike him and also makes it difficult for him to be friends with people. He also struggles to connect with people because of his actual age, with him often appearing to be mentally stuck in the time of his youth, making him say and do things people don't really do anymore.
However, underneath all this attitude is a good person who simply wants to find his place in the world and resist his vampire insticts, with his attitude mostly being because he is still in the body of a teenager. While it took time, the people he considered to be his friends eventually grew to find his antics amusing, with even Nina finding his flirting to be funny. However, like Mitchell he has a dark side because of what he is, which often manifests in the desire to find excuses to kill people, such as claiming he will do it to bring Matt's murder to justice.
- Yvonne Bradshaw: Yvonne is Adam's wife and his love, but at first he wasn't sure if it was real. This is because she is a succubus, and her touch makes any male fall in love with her, but she ends up killing those she has sex with. Adam only survived because he was already dead. When he learned the truth, Adam was upset and began responding about it in a rude way, trying to appear that he wasn't affected. However, Annie made him realise that he honestly loved Yvonne and returned to her. It can be presumed that they are still in love as they got married.
- John Mitchell: At first, Mitchell wanted nothing to do with the youthful vampire, seeing him only as a risk to a life clean of blood. In contrast, Adam at first wished to be taught by Mitchell to control his thirst and be safe. This is mainly because he hasn't met another vampire since he was turned. However, Adam soon abandoned any attempts of friendship after seeing that Mitchell won't help. Despite still not getting along however, in the end Mitchell gave Adam money and some advice when he decides to try and be clean by himself, telling him to surround himself with good people. This change in attitude possibly happened because Mitchell saw himself in Adam.
- George Sands
- Nina Pickering
- Annie Sawyer: Like with Nina, Adam constantly flirted with the ghost in ways that made her uncomfortable. Despite embarrassing her, Annie doesn't appear to suffer any grudge against Adam, though she was mildly annoyed when he returned. It appears that they are good friends however.
- Christa Stammers: First meeting at the school cafeteria, the two at first didn't see eye to eye. Even though they worked together while investigating Matt's death, they still had a slightly antagonistic relationship. However, through Christa working as his moral constraint and Adam at times making her laugh through his humour, the two developed a friendship that had hints on a romantic one, which Matt suspected. It is unknown what their relationship is like now however, seeing as Adam left the group.
- Matt Bolton: At first, Adam only showed some signs of sympathy towards Matt, generally being rude and offensive whenever Matt acted as his friends. At numerous points, they relationship became a struggle because of how Matt wanted revenge and nearly led Adam to killing an innocent girl. However, later they have developed a friendship, with Matt finding Adam to be the only person he wants with Christa and Adam's insults starting to seem to be a fond sign of their friendship, with it shown that Matt was developing Adam's sense of humor near the end. Another sign of their friendship was that, having just said he was not his mate a few hours prior, Adam told Matt that it has been fun hanging out with him. It is unknown what their relationship is like now, as Adam had left the group at some point.
- Mr Roe: Adam at first didn't think much of Roe, seeing him only as a lowly teacher who does what other people tell him to do. However, upon learning that Roe killed Matt, Adam quickly went to kill Roe, but was stopped by Matt and Christa.
- He is the "Mitchell" of Being Human's online spin-off Becoming Human.
- Adam has met all of the main characters on Being Human except for Alex and Rook. This puts him behind Tom, who has met all the main characters, and Annie, who has met Alex.
- Craig Roberts, who plays Adam, also had the role of Robin Branagh in Young Dracula, who was a vampire fan and the best friend to the main character Vlad, who was a vampire.