The first trailer for "Avengers: Age of Ultron" was attached to Christopher Nolan's science-fiction film "Interstellar," which debuted on November 7, 2014. The trailer was leaked online before its intended public debut at the end of an episode of the TV show "Marvel's Agents of SHIELD."
The trailer for "Avengers: Age of Ultron" debuted at the San Diego Comic-Con International to a standing ovation and was highly praised by critics and Internet message boards. The vocal performance of James Spader as the movie's titular villain, featuring a sinister spin on a classic song from "Pinocchio" that audiences interpreted as a nod to Marvel's recent acquisition by Disney, received particular praise.
A low-quality illegal capture of the trailer was immediately leaked online. Marvel released a high-definition version of the trailer soon after and joked about the situation on Twitter, blaming the comics' fictional terrorist group HYDRA for the leak. While the trailer made its theatrical debut before "Interstellar," it was soon shown before a variety of other movies. Marvel ultimately released four full-length trailers for the film, as well as a number of brief clips and featurettes about the characters. "Avengers: Age of Ultron" arrived in theaters on May 1, 2015.