The UNIT Club Page, later known as the UNIT Hotline, was an in-universe feature printed in Doctor Who Weekly, later Doctor Who Monthly and Doctor Who Magazine, from issues 26 to DWM 47. The first published feature included an address and instructions on how to "join UNIT," with those who followed instructions being sent a codebook and ID card. Following issues would feature coded messages which could be cracked with the codebook, alongside other smaller features giving "intel" to the undercover UNIT operatives. The feature returned in the celebratory issue 350.