Genis-Vell is a superhero appearing in American comic books published by Marvel Comics. Created by Ron Marz and Ron Lim, the character first appeared in Silver Surfer vol. 3 Annual #6 (1993). Genis-Vell is the son of superhero Mar-Vell and the brother of superhero Phyla-Vell. The character has also been known as Legacy, Captain Marvel, and Photon at various points in his history.

Genis-Vell debuted in Silver Surfer vol. 3 Annual #6 (1993) under the codename Legacy, created by writer Ron Marz and artist Ron Lim. He appeared in the 1994 Cosmic Powers miniseries. He appeared in the 1995 Captain Marvel series, his first solo comic book series, by writer Fabian Nicieza and artist Ed Benes. It was cancelled after six issues. He appeared in the 1995 Avengers Unplugged series. He appeared in the 1998 Avengers Forever series. He appeared in the 1997 Thunderbolts series. He appeared in the 1999 Captain Marvel series, his second solo comic book series, which lasted for 35 issues until October 2002.

Genis-Vell appeared as part of the U-Decide initiative in the 2002 Captain Marvel series, by writer Peter David. It was cancelled after 25 issues. He appeared in the 2022 Genis-Vell: Captain Marvel series, also written by David.

After the death of Mar-Vell (Captain Marvel), his lover Elysius decides to have a son. As one of the Eternals living on Titan, she uses the advanced technology of her race to impregnate herself using Mar-Vell's genetic material. Elysius seeks to protect her new son, Genis-Vell, from Mar-Vell's powerful enemies by taking him to a distant planet. There, she artificially ages him and implants false memories in his brain, making him believe that he had a natural childhood and that he is the son of Starfox.

Elysius, like her son, was created artificially. Elysius was created by the Titan computer ISAAC, which had been corrupted by Thanos.

When the Destiny Force resurfaces in Rick Jones for a second time (the first time occurring during the Kree-Skrull War), it triggers a time-spanning conflict known as the Destiny War. A motley crew of Avengers are gathered. Among them is a future version of Genis, now known as Captain Marvel, eventually revealed to have been selected because of the role his interaction with Rick would play in shaping the final outcome of the battle. At the climax of the Destiny War and with Rick's life in jeopardy, Genis recreates the Nega-Band connection with Rick to save him. After the war, Rick returns to the current day and is inadvertently bound to Genis, triggering the latter's latent cosmic awareness.

Rick and Genis spend a considerable time adventuring together, in an arrangement somewhat reminiscent of the one that existed between Genis' father, Mar-Vell, and Rick years before. While they were bound, Mar-Vell and Rick exchanged places between the regular universe and the Negative Zone and shared a telepathic bond. Genis-Vell and Rick, however, alternate between the regular universe and the Microverse. In addition to their telepathic bond, the two can see each other in reflective surfaces or as red ghostly visions.

Whereas Mar-Vell and Rick formed a strong friendship during their time together, Genis-Vell and Rick have a much harder time getting along. Genis' alien (and immature) perspective make him unfathomable to Rick's jaded-sidekick sensibilities. Their ability to see and hear what the other is experiencing lead to awkward situations with Rick's wife, Marlo Chandler, and Genis' many amorous partners. Eventually, however, they become good friends.