When Barry Allen and Oliver Queen (guest star Stephen Amell) wake up one morning and realize they have swapped bodies with each other, the two set off to find out what disturbed the timeline to cause such a shift. However, things quickly go from bad to worse when they present their case to Team Flash and the gang doesn't believe them. Barry and Oliver realize they need Supergirl's help and travel to Smallville on Earth-38 where they end up meeting Kara's cousin, Clark Kent (guest star Tyler Hoechlin), and intrepid reporter, Lois Lane (guest star Elizabeth Tulloch).
Episodes Comprise: - The Flash: Season 5, Episode 9 'Crisis on Elseworlds' (Part 1)
- Arrow: Season 7, Episode 9 'Crisis on Elseworlds' (Part 2)
- Supergirl: Season 4, Episode 9 'Crisis on Elseworlds' (Part 3)
The storyline in itself is not that difficult to follow; what is difficult is, that unless you are au fait with the full back story of the characters Green Arrow, Flash and Supergirl, and their interactions (if indeed they do interact in "DC World") things become a bit confusing as to who is what and, most pertinently, where. Rather disappointing overall but has a clever trick of having episodes from the 3 series interwoven as one storyline, but my original statement overrides that as you could very easily have had 3 standalone episodes of a mini-series, given that all the characters are involved in all 3 'episodes'