The "Strip That Down" singer and "The X Factor" U.K. judge have teamed up to watch some of the country's favourite TV shows and give their opinions on them as part of the Stand Up To Cancer special on Friday, October 26.
Liam shared a picture on Instagram of the duo relaxing on a sofa in front of the TV armed with a remote control and snacks.
"Tune into @channel4 on Friday night from 7pm to watch me and @louist91 on #gogglebox for #StandUpToCancer. It's for a cause that's close to our hearts, so please give it a watch and donate (heart emoji)," he wrote in the caption.
The cause is particularly significant to Louis, who lost his mum Johannah Deakin in December 2016 after a battle with leukaemia.
This marks the second time the duo, who have been pursuing solo projects since One Direction went on hiatus in early 2016, have reunited recently, after Liam helped Louis picked his final contestants at the Judges' Houses stage of "The X Factor".
Other famous faces to appear on the special include soccer star Peter Crouch, wife Abbey Clancy and her dad Geoff.