In Paris in May 1968 he met Australian singer, guitarist, poet and ex-Soft Machine member Daevid Allen, with whom he was to start Gong, an international community band incubated in Deya, Majorca, that toured France and Europe before appearing on the British scene starting at the first Glastonbury festival in June 1971.
Virgin Records signed them in 1973, and their album Camembert Électrique appeared in the charts. Gong toured extensively around the UK and Europe while producing the albums of their "Radio Gnome trilogy": Flying Teapot, Angel's Egg and You. Malherbe was often billed as "Bloomdido Bad de Grass". In 1975, when Allen left Gong, Malherbe along with Steve Hillage, Mike Howlett, Pierre Moerlen, Miquette Giraudy as Gong recorded 1975's Shamal. Hillage and Giraudy departed soon after. 1976's Gazeuse! featured Alan Holdsworth and Mino Cinelu in their place. Mike Howlett departed after the recording of that album.
Malherbe's turn to leave Gong came in 1978, when they changed their name to Pierre Moerlen's Gong. Back in France, he put together his five-piece Bloom band; in 1980 he released an album on EMI which was rather jazz-rock in style. The most significant change of 'shape' came in 1994 with the start of his association with multi-instrumentalist Loy Ehrlich, and percussionist Steve Shehan performing his own brand of wind-led, acoustic ethnic-jazz. Under the name Hadouk Trio the band has toured and played with many artists in Europe, while Malherbe himself has continued to perform individually and with other artists (particularly Brigitte Fontaine and guitarist Pierre Bensusan) in Japan and the U.S. In 2006 Hadouk released an album with pioneer American trumpeter Jon Hassell, Utopie.
Malherbe and Daevid Allen began collaborating again with Gongmaison in 1989, which eventually began performing and recording again under the name Gong on the studio albums Shapeshifter (1992), Zero to Infinity (2001), and 2032 (2009) after rejoining with various members of the classic line-up, including Gilli Smyth and Mike Howlett, among others. Malherbe has also joined them on various tours, and has appeared with Gong and Hadouk at all Gong Family Unconventional Gatherings in 2004 and 2005 at the Glastonbury Assembly Rooms, and 2006 at the Melkweg in Amsterdam, at which Gong's set was filmed and released as a DVD.