David Duchovny kissed his The X-Files costar Gillian Anderson at New York City’s The Cutting Room Tuesday night after singing together.

David Duchovny, Gillian Anderson Kiss

Duchovny was holding the concert in NYC to promote his debut album, Hell or Highwater. After Duchovny played some of his own tracks, Anderson asked him, “Can we play some real music please?” In response, Duchovny started on Neil Young‘s “Helpless” with Anderson singing backing vocals.

At the end of the performance, Duchovny planted a friendly kiss on his costar and longtime friend. Duchovny and Anderson, though always insisting that their relationship is strictly platonic, have often been the subject of dating rumors. Responding to the suggestion recently, Duchovny quipped at NBC’s Summer Press Day, “Oh yea, we live together!”

Duchovny and Anderson, who played Mulder and Scully on The X-Files, are reuniting for a reboot of the show. The six-episode event series will kickoff with a two-night premiere Sunday, Jan. 24, 2016 at 10 p.m.