An Australian-trained script-writer who began writing scripts for soap opera Home and Away, Holly Lyons moved to the UK to work, beginning with scripts for soap opera Emmerdale Farm (1999-2004). She followed this with work as script and story editor for 24Seven (2001-2002), a teen drama set at a boarding school; scripts for The Story of Tracy Beaker (2003), a children's program about an imaginative young girls living in a children's home; scripts and work as script editor for Girls in Love (2003), a children's series based on UK author Jacqueline Wilson's books; scripts for My Parents Are Aliens (2003), a children's program about orphans whose foster parents are stranded extra-terrestrials; work as script editor on Seriously Weird (2002-2004), a British-Canadian co-production; scripts for animated children's shows Fireman Sam (2005) and Horrid Henry (2006); work as script editor on My Life as a Popat (2007), in which thirteen-year-old Anand Popat turns his life into a series of comic fantasies; scripts for Welsh-English co-productions Holi Hana (2007-2008) and Igam Ogam (2009); scripts for My Almost Famous Family (2009); scripts for BAFTA-nominated children's comedy-drama Sadie J (2011); and scripts for BAFTA-nominated children's sit-com Dani's House (2008-2011).

In 2004, Lyons and Andy Watts co-created Help! I'm a Teenage Outlaw, an anachronistic, pseudo-historical children's television drama in which twelve-year-old Tom York inherits the family business--of highwaymanning.

Lyons also worked as script editor for Australian/Scottish co-production Jeopardy, a TV series about alien encounters: Lyons was the only Australian script-writer working for the program.

As of 2012, she is again writing scripts for Home and Away.