Cyber Security Challenge UK is asking members of the public to showcase their digital skills and help investigate suspicious emails linked to a mysterious cyber-crime group.
The competition has been developed by the National Crime Agency (NCA). The Opening Lines challenge is the first competition of the 2014/15 programme of online and face-to-face cyber battles, aimed at uncovering the best UK amateur security talent.
This latest set of competitions sees the introduction of a new enemy - The Flag Day Associates - the Challenge's first recurring characters that will underpin the coming year's challenges. The group will feature prominently in a "gripping storyline", culminating at the 2015 Masterclass next March.
The fictitious Flag Day Associates first appeared at the end of the Masterclass awards ceremony in March this year, via a threat video featuring three masked individuals warning of a future cyber attack on the UK.
The video was uploaded to YouTube and further secret details embedded within it were uncovered by Challenge candidate Joe Harris, a finalist in the 2013/14 competitions.
His analysis of the video file revealed a possible date of the cyber attack, and a reference to the next solar eclipse observable from the UK.
"The fifth Cyber Security Challenge will be the first time we have brought all our activities and competitions under a single scenario that will evolve with twists and turns over the coming year," said Challenge CEO Stephanie Daman.
"By creating a mischievous, and above all realistic nemesis to defend against, the fifth Cyber Security Challenge will be the most eventful and action packed so far, and will help to really excite, inspire and grow our candidate community."
Candidates will be briefed on a cyber attack situation and be asked to provide analysis and report back to officers at the NCA's National Cyber Crime Unit.
The National Crime Agency's Adam Kramer, who developed the challenge said: "The aim of the Opening Lines is to test the skills required to investigate cyber crime and the individuals or groups responsible for it.
"Whether it's the creation and spread of malicious software, or attempting to steal banking details, those charged with investigating cyber crime need to have the technical ability, knowledge and understanding to defend the UK and its citizens from cyber related attacks."
He said he hoped the new challenges will test those who may want to pursue careers in cyber crime investigations.
The highest ranked entrants within the Opening Lines assignment will qualify for the first of the Challenge's new set of face-to-face cyber battles. These one-day events will run throughout the remainder of the year, and will determine the final line up of online defenders chosen to defeat the Flag Day Associates at the Masterclass final next year.