Scientists are switching to the 'dark side' this weekend as they prepare to ramp up the power at the Large Hadron Collider (LHC).
After capturing a species of Higgs boson, the particle hunters now have their sights set on a new trophy – dark matter.
A race is on between groups at the LHC, the world's biggest particle accelerator, and other scientists operating in space and deep underground who are chasing the same discovery.
Dark matter is invisible "stuff" that holds galaxies together with gravitational glue but defies common sense by being undetectable by any direct means.
It is thought to make up around a quarter of the mass-energy in the universe.
Finding it would be a major coup, second only to detecting the Higgs boson, the elementary particle believed to be responsible for mass.
It will be a top priority when a revamped and almost twice as powerful LHC is switched back on in March 2015 after a two-year shutdown and refit.
The €3bn machine fills a 27-kilometre circular underground tunnel that straddles the border of France and Switzerland near Geneva.
Dr David Newbold, a member of the CMS (Compact Muon Solenoid) detector experiment at the LHC, said: "There's a real conflict between astronomy, which says dark matter is there, and particle physics, which hasn't found anything yet. This has been the big surprise, nature's failure to put dark matter in a place where we can find it."
The pressure is on the LHC after possible signs of dark matter came from a laboratory buried 2,600 feet underground in a US mine on Monday.