Geoffrey "Geoff" Campbell is a fictional character from the Australian soap opera Home and Away, played by Lincoln Lewis. The actor spent two years auditioning for a role on the show, before he was offered the part of Geoff. He was surprised to get the part as he thought his audition had not been very good. Lewis relocated to Sydney for filming and he cut his long hair for the character. His casting was announced on 17 June 2007, while he made his first screen appearance during the episode broadcast on 20 June 2007. After two years on the show, Lewis quit Home and Away and filmed his final scenes on 18 September 2009. The character made his screen exit on 12 February 2010.

Geoff was portrayed as being an innocent, honest and sensible teenager throughout his duration. Geoff was a devout Christian and a rugby league footballer. He and his sister Annie (Charlotte Best) were raised by their religious grandfather, Bruce (Chris Haywood) on the family farm, following their parents deaths. Due to his upbringing, Geoff's social skills were not the same as other teenagers his age. Geoff developed an "on and off" friendship with Aden Jefferies (Todd Lasance) and his storylines often revolved around his romantic relationships. Geoff's first love interest was the equally inexperienced Melody Jones (Celeste Dodwell). He then dated Nicole Franklin (Tessa James) and lost his virginity to her, while they were stranded on an island. Geoff also dated Claudia Hammond (Alexandra Park) and was led to believe that he was the father of her baby. For his portrayal of Geoff, Lewis won the Most Popular New Male Talent Logie Award.

On 17 June 2007, Angela Cuming of The Sun-Herald reported Lewis had joined the cast of Home and Away. The actor had previously auditioned for a role on the show for two years, before finally impressing the producers. During an interview published in Inside Soap, Lewis revealed that he had auditioned for Ric Dalby in 2004, making it down to the final three, before Mark Furze got the part. Then in 2007, Lewis auditioned for Drew Curtis and made it to the final two – only for Bobby Morley to be given the role. Of the moment he learned he had secured a role in Home and Away, Lewis said "I was in a furniture shop with my mum and aunty when [the producers] called to say I had got the job. I started screaming and running around. I am just so stoked to be here doing this and it still hasn't really sunk in yet." Lewis was surprised to get the role of Geoff as he thought his audition had been "terrible". Lewis relocated to Sydney, where Home and Away is shot, and he had to cut his long hair short for the part. Lewis made his screen debut as Geoff on 20 June 2007.

Prior to his introduction, Geoff was described as being a farm boy, a football player and Summer Bay High's newest student. Carolyn Stewart from TV Week thought Geoff was an innocent, sporty teenager. Lewis stated that the first thing he knew about Geoff was that he was a rugby league footballer. He was "over the moon" as football and acting were two of his passions in his life. The actor thought Geoff's best quality was his honesty, but observed that his social skills were not up to "a normal teenager's standards". A writer for the show's official website described Geoff as being "sensible and serious" and having a "grim, hard-working life". Geoff was a devout Christian, who planned to become a priest when he grew up. Lewis commented that while he was not as "diehard religious" as Geoff, he did believe. He added "Playing this character has been an eye-opening experience for me, as it's allowed me to see things from the perspective of someone who's very strong in their beliefs."

Geoff and his sister Annie (Charlotte Best) were raised by their "super-religious" grandfather, Bruce (Chris Haywood), after their parents died in a car crash. The loss of his parents and the firm hand of his grandfather, helped to shape Geoff into "a very responsible boy who is black and white about right and wrong." Geoff, Annie and Bruce lived at the family farm on the outskirts of Summer Bay and Bruce home-schooled the siblings. However, Geoff was later sent to an all boys boarding school for two years. Lewis agreed that he and Best had a "natural brother-and-sister chemistry" on-screen because they both have siblings in real life and were able to relate to one another. He also said that he and Best got on great and enjoyed "taking the mickey" out of each other like a real brother and sister.

Geoff's love of football and his faith made him stand out from other guys his age. He developed an "on and off" friendship with Aden Jefferies (Todd Lasance). Aden disliked Geoff at first due to the fact that Geoff was more talented at football and to Aden, represented "the hypocrisy of society." Aden was convinced that Geoff was just "as flawed as everyone else, and just as full of sin." The two eventually matured and became friends. Off-screen, Lasance and Lewis were close friends and while they lived together, they learned lines and critiqued each other's performances. After dropping out of school, Geoff found himself at a loose end and thought he and Aden could work together on a prawn trawler. Geoff believed that it was just the thing to pull Aden "out of his funk" following the death of his wife. Aden and Geoff found working together harder than they anticipated and their tempers soon got the better of them. When they clashed over how to repair the trawler, Geoff lashed out and punches were thrown. They both came into contact with the trawler's electric wiring, which left Geoff having to rescue Aden. Lewis loved the constant feud between his and Lasance's characters. He admitted that they would "amp it up" as much as they could.

Because of Geoff's background, he was "completely clueless" when it came to girls. He was insecure, but he eventually shared a kiss with the equally inexperienced Melody Jones (Celeste Dodwell). Lewis thought that Geoff and Melody were similar as they were both naive and had sheltered upbringings. Nicole Franklin (Tessa James) took advantage of that and convinced Geoff that Melody "dumped him" because their first kiss was so bad. Nicole told Geoff that if he wanted Melody back, then he would have to become a better kisser and she offered to teach him. Geoff became determined to work things out with Melody and accepted Nicole's help. Speaking to an Inside Soap columnist, Lewis explained "Geoff thinks something's not right about it – surely Melody wouldn't ditch him after just one bad kiss? But every time he sees Melody now, she's stand-offish." Unbeknownst to Geoff, Melody was under the impression that he was being unfaithful to her with Nicole. Having seen them both together, Melody jumped to the wrong conclusion. Nicole did not correct her and went out of her way to stir up trouble. Nicole was frustrated that Geoff was not falling for her, so she set out to sabotage his relationship with Melody instead.

Geoff became involved in "a sordid love triangle" with Melody and Nicole, which left viewers guessing which girl he would end up with. Geoff and Nicole eventually began dating. James thought Nicole was the one for Geoff, but Geoff might not be the one for Nicole. Lewis believed that his character had "deep feelings" for Nicole. During an interview published in Inside Soap, James said Geoff and Nicole were complete opposites, but it worked in their favour. She called their relationship "fiery" and thought they had been through a lot together. Lewis commented that Geoff and Nicole were very similar in some of their traits, as they were both stubborn and opinionated. He told Jason Herbison that when Geoff first started dating Nicole, he had a lot of parents and grandparents tell him that Geoff should be with Melody instead, because Nicole was not a good influence. James believed that if Geoff and Nicole broke up, they would still stay good friends. While Lewis added that as long as Geoff and Nicole wanted to be together, they could work through anything.