The Flash Finally Unites Two Beloved DC Characters on Screen

The Flash wraps up its opening holiday weekend today, and most of the conversation around the movie has centered on the multiversal cameos that shaped its plot. Some of those cameos were more surprising than others, and among those were a pair of characters that fans have long waited to see onscreen together. Before now, it didn't seem like something that was ever likely to happeen. Here's your last warning, folks: spoilers ahead for The Flash, in theaters now. Decades after the last time either actor donned a cape onscreen, The Flash finally put Christopher Reeve and Helen Slater onscreen together as Superman and Supergirl.

Reeve was the original big-screen, big-budget superhero, appearing in four Superman movies between 1978 and 1987. In 1984, as Reeve's Superman franchise was starting to lose steam, Slater starred in Supergirl, a big-screen spinoff with direct-to-video production values. The movie firmly established itself as part of the same universe as the Reeve movies by including an appearance by Marc McClure as JImmy Olsen, but Reeve's Superman was nowhere to be found.

Reeve was originally supposed to make a cameo in Supergirl, but bowed out early in production, with Superman's absence being explained by news broadcast saying he's in space on some kind of peacekeeping mission. After Superman IV: The Quest For Peace effectively killed the franchise, Reeve would go on to appear in Smallville as a nod to his heroic legacy. Slater has appeared in a number of DC projects, playing Talia al Ghul in Batman: The Animated Series, Superman's mother Lara-El in Smallville, Supergirl's adoptive mother Eliza Danvers in The CW's Supergirl, and Martha Kent in DC Super Hero Girls: Hero of the Year.

Reeve passed away in 2004, so his cameo -- like those of Adam West and George Reeves -- was done with CGI. It isn't clear whether Slater provided a performance for the CGI to track for her cameo, or whether she just signed off on a CGI body double being used.

The Flash speeds into theaters on June 16th, promising to reshape the DC Multiverse with the help of familiar faces and brand-new heroes. Barry Allen (Ezra Miller) ventures to the past to change history, resulting in massive repercussions for the future. Forced to team up with another version of Barry, the mysterious Kryptonian known as Supergirl (Sasha Calle), and the iconic Batman (Michael Keaton), the Scarlet Speedster is forced to reckon with his mistakes and save a doomed reality. The Flash is directed by Andy Muschietti, written by Christina Hodson from a story by Joby Harold, and produced by Barbara Muschietti.