Gardner was overjoyed to see the cast members he worked alongside from 1999 to 2006 attend the play he’s currently starring in.
They all posed together following Gardner’s performance in the Lyric Hammersmith Theatre’s Accidental Death of an Anarchist.
Appearing in the photo were Alex Kew, who played Josh Barker, Charlotte Francis, who played Lucy Barker and Olisa Odele, who starred as CJ.
Stephanie Fearon, who joined the show as Harriet after original star Danielle McCormack left, was also present, as was Jordan Maxwell, who played Frankie Perkins.
Gardner, who was beaming in the photo surrounded by his former cast members, wrote on Twitter on Wednesday (23 March): “My Parents are Aliens reunion at the play tonight. Such a wonderful group of friends.”
My Parents are Aliens ran from 1999 to 2006, airing 106 episodes in total. The CITV series originally starred Tony and Barbara Durkin as alien foster parents, Brian and Sophie Johnson.
Carla Mendonça replaced Durkin from 2001.
Gardner recently addressed claims that ITV series The Larkins had been cancelled.
The Last Tango in Halifax actor was responding to reports that the series, which stars Bradley Walsh, would come to an end due to low ratings.