In February, Josh Anderson and Ryan McLachlan, played by Jeremy Angerson and Richard Norton, respectively, made their first appearances.
Beth Buchanan began playing Gemma Ramsay, the niece of established character Madge Bishop in June.
The following months, three more members of the new Willis family arrived, Doug, Pam and Adam, played by Terence Donovan, Sue Jones and Ian Williams, respectively.
Alison Whyte guested as environmentalist Amber Martin in September and Richard Huggett arrived as Glen Donnelly.
Writers devised relationship stories for Caroline alongside the characters Adam Willis (Ian Williams) and Jim Robinson (Alan Dale).
[2] A notable storyline for the character was kissing her sister Christina's (Gayle Blakeney) husband Paul Robinson (Stefan Dennis).
[6] Fletcher is a British actor and had appeared in Neighbours four times prior in small "walk on" roles as delivery men.
Fletcher told that Stuart Gilles from Manchester Evening News that he had an ironic first day filming because he had a series of clumsy accidents.
Fletcher told Gilles that Kelvin "always fancied" Melanie but believed she would not want a "bashful type" as a romantic partner.
Melanie gives Kelvin too much confidence and he asks Christina Alessi (Gayle Blakeney) out to dinner and goes on a date with Andrea (Bridie Carter).
Joshua "Josh" Anderson, played by Jeremy Angerson, made his first on-screen appearance during the episode broadcast on 5 February 1990.
Norton told Chrissie Camp of TV Week that he "couldn't believe his luck" when he received the role of Ryan.
[16] James Cockington from The Sydney Morning Herald reported that the British actor had joined the cast in a guest role.
She thinks she will need to fly back to the US and asks Madge and Harold to find Lord Ledgerwood and secure her business deal.
[20] Dorothy lived on Ramsay Street alongside her niece Tiffany (Amber Kilpatrick) and nephew Ryan McLachlan (Richard Norton).
[13] In 1993, Dorothy meets Tom Merrick (Robert Essex), a school inspector who comes to evaluate Erinsborough High and they fall in love.
[21] Edward "Eddie" Buckingham, played by Bob La Castra, made his first screen appearance during the episode broadcast on 2 April 1990.
[22] La Castra was written out of Neighbours in October 1990 along with a series of characters, so the producers could make a return to focusing on family-oriented drama.
[22] Gary "Boof" Head, played by Stephen Hall, made his first screen appearance during the episode broadcast on 19 April 1990.
Caron Eastgate from TV Week reported that Boof would be responsible for the breakdown of Todd Landers (Kristian Schmid) and Melissa Jarrett's (Jade Amenta) relationship.
[24] Boof is introduced during a bike race alongside established characters Todd, Melissa, Ryan McLachlan (Richard Norton), Josh Anderson (Jeremy Angerson) and Cody Willis (Amelia Frid).
Boof threatens to hurt Toby's dog Bouncer and kidnaps him as leverage, holding him hostage in a metal shed at a scrapyard.
After Marco secretly rescues Bouncer from the scrapyard, Rick and Toby bring Cameron Hudson's (Benjamin Grant Mitchell) motorbike to Boof.
He appears to foil a robbery but it is later discovered that he and another group member, Clay (Russell Frost), staged the whole thing in order to get publicity in the paper from Cameron, who is a journalist.
[27] Douglas "Doug" Willis, played by Terence Donovan, made his first screen appearance during the episode broadcast on 18 July 1990.
Pamela "Pam" Willis (previously Beresford), played by Sue Jones, made her first screen appearance during the episode broadcast on 6 August 1990.
[31] Trained as a nurse, Pam arrives as a full-time mother to her four children: Adam (Ian Williams), Gaby (Rachel Blakely), Brad (Scott Michaelson) and Cody (Amelia Frid).
[34] Writers devised romance storylines for the character involving Caroline Alessi (Gillian Blakeney) and Gemma Ramsay (Beth Buchanan).
Amber is an environmental activist who arrives in Erinsborough to visit her lifelong best friend of Kerry Bishop (Linda Hartley-Clark).
Amber learns that there is a duck hunting session being held in marshlands and asks Kerry to join her and form a protest against the hunters.