For nine days, some of the best in track and field will gather in Beijing to battle for supremacy in 47 events. Here are five outstanding events and the main protagonists.
MEN'S 100M (TOMORROW)
Can history's fastest man beat this year's fastest man? That is the mouth-watering prospect as Usain Bolt, chasing his fourth straight 100m world title, takes on Justin Gatlin, the former world champion and disgraced American sprinter. Gatlin has served two doping bans but, at 33, looks in the best shape of his life and has posted four of the season's best timings. Despite some niggling injuries in the past two years, Bolt will want to show he remains the king of the track.
MEN'S TRIPLE JUMP (MON)
Only three men (world record-holder Jonathan Edwards, 1996 Olympic champion Kenny Harrison and 2013 world champion Teddy Tamgho) had cleared 18m in the past 20 years until Cuban Pedro Pichardo and American Christian Taylor added their names to that list this season. The pair did it on five occasions, with the 2012 Olympic champion Taylor maintaining a 3-2 edge. Edwards' 18.29m world record could come under serious threat.
MEN'S 800M (TUES)
Once the exclusive domain of David Rudisha, the world record holder and 2012 Olympic champion, the race is more open now after the Kenyan, 26, was hit by injuries. He has also lost his last six races against his Botswana rival Nijel Amos, 21. Another to watch is Bosnian Amel Tuka, 24, who has clocked the season's fastest time and has already beaten Amos and defending world champion Mohammed Aman of Ethiopia.
MEN'S 200M (THURS)
At 1.96m, Bolt's height should give him the edge over the longer distance but has yet to hit his stride in this event, with a pedestrian 20.13sec - almost a second slower than his 19.19sec world record - set in May for his year's best effort.
In contrast, Gatlin has gone below 20sec four times in 2015.
WOMEN'S 200M (FRI)
Singapore's sole representative, Shanti Pereira, makes her World Championships debut but do not expect the 18-year-old schoolgirl to progress beyond the heats. The SEA Games champion's 23.60sec personal best does not place her among the year's top 226.
The race has been thrown wide open with 2012 Olympic champion Allyson Felix opting out - leaving fellow American Candyce McGrone and Dutchwoman Dafne Schippers to seize the initiative.