In 1988, after four years with the German power metal band Helloween, guitarist and songwriter Kai Hansen decided to leave the group.

The original lineup released the album Heading for Tomorrow in February 1990[3] and, later that year, the Heaven Can Wait EP, with new guitarist Dirk Schlächter and new drummer Uli Kusch.

With some brand-new songs written, Gamma Ray entered the studio under the supervision of producer Tommy Newton and recorded their second album Sigh No More, which was released in September 1991.

[3] The style differed vastly from that of Heading for Tomorrow, featuring darker lyrics inspired by the Persian Gulf War that was raging at the time.

[3] After the Japanese tour at the beginning of 1991, Gamma Ray underwent another personnel change: the rhythm section (Wessel and Kusch) left due to a personal disagreement and were replaced by Jan Rubach (bass) and Thomas Nack (drums), both from the Hamburg band Anesthesia.

Vocalist Ralf Scheepers, who lived far away from the other band members hometown of Hamburg, attempted to become the new Judas Priest singer after Rob Halford left.

He could not really make up his mind to move to Hamburg and there was one problem with that because when we wrote the songs I was always trying to think of his voice but on the other hand it would have been a lot better if he write his own vocal lines, melodies and lyrics.

[sic] [4]Hansen then began to search for a new vocalist but, due to demand from friends and fans, took on the guitar-vocal duties himself as he had done for Helloween's first EP and album.

In a 2008 interview, Hansen spoke about the importance of the Land of the Free album and what it represented:We made it exactly at a time point when this kind of metal was proclaimed to be dead as can be.

Jan Rubach and Thomas Nack both left in order to return to Anesthesia, with Gamma Ray recruiting new drummer Dan Zimmermann.

The setlist contained songs drawn from all of their albums up to Majestic (excluding Insanity and Genius) and also a cover of the Helloween hit "I Want Out".

In recent years, Gamma Ray have made use of touring keyboard players to fully augment their sound in a live environment.

Axel Mackenrott of Masterplan fulfilled these duties in the past and was followed by Eero Kaukomies, a Finn who also plays in a Gamma Ray tribute band named Guardians of Mankind.

[8] Heikkinen also shared stage with fellow axemen Hansen and Richter making "a three-guitar special" for the encore numbers at the Nosturi club in Helsinki, Finland, on 29 March 2010.

To promote the album, Gamma Ray were the "very special guest" on Helloween's Hellish Rock 2007/2008 World Tour, on some shows along with the band Axxis.

For the final encores of the evening, Hansen and members of Gamma Ray joined Helloween to play a couple of songs from when he was in the latter band.

It was released on 29 January 2010 to modest critical praise, but disappointed some fans, who felt that it was uninspired and a weaker effort than Land of the Free II.

[12] Kai Hansen revealed, in an interview with Metal Blast in April 2013, that their eleventh album, Empire of the Undead, would have a "more thrashy" sound.

[15][16] In June 2021, on the Scars and Guitars podcast, Kai Hansen stated that, despite his reunion with Helloween, he is not letting Gamma Ray die, and that he is preparing material for a new album to be tentatively released in 2022.

[17] In 2023, Gamma Ray released a newly remastered version of Blast from the Past in a limited 3-CD digipak (which includes the Skeletons & Majesties EP), digitally, and on vinyl LP.