Invasion! (Arrowverse)

Lore & Background

The crossover begins with Barry Allen investigating a meteor crash that reveals a Dominator spaceship. Lyla Michaels explains the Dominators landed on Earth in the 1950s but departed. Barry assembles Team Arrow, the Legends, and Supergirl to train against the aliens. Cisco Ramon discovers a message from Barry's future self exposing his timeline manipulation, causing most of the team to lose trust in Barry. After the Dominators abduct and kill the President, they use a mind control device to turn several heroes against Barry and Oliver, who eventually free them. The Dominators then abduct Sara Lance, Ray Palmer, John Diggle, Thea Queen, and Oliver, placing them in a shared hallucination of a simulated reality. The captives escape after defeating personifications of their enemies. The team learns the Dominators are gathering information on metahumans to build a weapon. The Legends travel to 1951 Redmond, Oregon, to kidnap a Dominator for information, learning the aliens assess humanity's threat due to metahumans and the Justice Society. The Dominators demand Barry's surrender, threatening a bomb that would kill all metahumans. The heroes destroy the bomb and force the Dominators to retreat using a pain-inflicting nano-weapon.

Reader's Guide

Invasion! marked the first Arrowverse crossover to include Supergirl, following the series' move to The CW. The event was praised for its character interactions and advancing season storylines, though the Dominators' motivations were criticized as unclear. Ratings were high, with each episode breaking viewership and 18–49 rating records, contributing to the most-watched week on The CW in six years. The crossover's production involved filming in October 2016, with scripts completed by September. The Arrow episode doubled as the series' 100th episode, featuring returns of actors from previous seasons. The event set a template for subsequent crossovers, such as Crisis on Earth-X the following year.

Did You Know?

• The crossover began with The Flash on November 29, 2016, not with the Supergirl episode 'Medusa' which aired the night before.
• The Arrow episode of the crossover doubled as the series' 100th episode.
• Melissa Benoist appears as Supergirl in The Flash and Arrow episodes of the crossover but does not appear in the Legends of Tomorrow episode.
• The Dominators' weapon is a bomb that would kill all metahumans on Earth.

Production & Development

The crossover's earliest seeds were planted back in 2014, when The Flash pilot first dropped hints of a multiversal threat lurking beyond Earth-1. Full adaptation efforts truly accelerated during the development of Elseworlds, and the title was finally unveiled to viewers at the close of that December 2018 episode. By mid-2019, casting announcements arrived, bringing in veteran DC performers such as Burt Ward and Kevin Conroy, while Cress Williams made her first Arrowverse crossover appearance from Black Lightning. Additional actors reprised roles from various DC films and television series. Principal photography wrapped between late September and early November 2019. The event extended well beyond the five CW series: a Black Lightning episode aired between the Batwoman and Flash installments, and a two-issue comic book explored characters and concepts the screen left out. The Supergirl, Batwoman, and Flash episodes premiered in December 2019, with Arrow and Legends of Tomorrow following in January 2020.

Narrative Scope & Story

The story pivots on the Monitor assembling a coalition of heroes—Green Arrow, the Flash, Supergirl, Batwoman, Sara Lance, Ray Palmer, and others drawn from across the multiverse—to confront the Anti-Monitor and his advancing antimatter wave, which has already annihilated countless parallel worlds. The prelude establishes enormous stakes: Barry learns his death is the price for saving billions, Oliver witnesses Earth-2's destruction firsthand, and the Pierce family on Freeland is torn apart by the wave. In the main event, the heroes race to evacuate Earth-38, battle Shadow Demons, and ultimately lose Oliver, who nullifies the Monitor to shield the exodus. The narrative then shifts to a multiversal hunt for the seven Paragons—Hope, Destiny, Truth, Courage, and Love—sending the team to Earths 96, 99, and 18. The Monitor's Paragon Detector identifies Kate Kane as Courage and Barry as Love, while Harbinger's secret contact with the Anti-Monitor introduces a betrayal thread. The culmination reshapes the Arrowverse, rebooting aspects of every series.

Reception & Cultural Impact

Critics responded favorably, singling out the event's sweeping scope, its bold ambition, and the sheer volume of cameos as standout strengths. The one notable point of contention was Oliver Queen's fate, which divided audiences and reviewers alike. Despite that, the crossover proved a ratings phenomenon: every episode delivered season highs for its respective show, underscoring the event's pull across the entire Arrowverse lineup. To capitalize on the momentum, The CW aired a two-episode aftershow called Crisis Aftermath, hosted by Kevin Smith, which dissected the crossover's events for viewers after parts one and three. The production also extended beyond television into print, with a companion two-issue comic book introducing characters and concepts the live-action episodes couldn't accommodate, broadening the event's footprint across DC media and giving fans additional narrative threads to explore.

Legacy & Continuity

The most far-reaching consequence of Crisis is that it rebooted elements of the entire Arrowverse, rippling through every series in the franchise. The event was originally slated to be followed by a 2021 crossover pairing Batwoman with the new Superman & Lois, but the COVID-19 pandemic derailed those plans. In its informal place, David Ramsey reprised his role as John Diggle across multiple Arrowverse shows, maintaining a thread of continuity without a full-scale event. The next true crossover, Armageddon, eventually arrived spanning the first five episodes of The Flash's eighth season in late 2021. The production also set a template for how the Arrowverse handled multiversal storytelling—layering prequel episodes, tie-in comics, and aftershows into a single event—establishing a blueprint that subsequent crossovers would build upon. The Monitor's role as architect of the crisis, and the Paragon framework he introduced, became foundational mythology for the franchise's future.