A broad range of intrinsic and innate immune mechanisms are in place in cells to defend against invading pathogens. Herpesviruses such as HSV-1 have evolved multiple mechanisms to antagonise such cellular defences. For example, promyelocytic leukaemia nuclear bodies (PML-NBs) are multiprotein complexes that can silence viral DNA, activate type I and II interferons and induce apoptosis. Other cellular proteins like IFI16 and DNA-PK can also restrict HSV-1 replication. To counteract these, HSV-1 encodes ICP0, an E3 ubiquitin ligase which has been known for many years to mediate dispersal of PML-NBs and degradation of a wide range of innate immune proteins. We recently found that pUL55, a poorly characterised tegument protein can also cause the disruption of PML-NBs and degradation of many of the same innate immune proteins in ICP0-null viruses. Using immunoprecipitation-mass spectrometry, we show that pUL55 forms a complex with two other viral tegument proteins: pUS10 and a viral protein kinase, pUL13, and that this complex can compensate for the absence of ICP0. Mutations preventing interactions between viral proteins in the complex, or inhibiting pUL13 kinase activity, prevent PML-NB disruption. Like ICP0, the triple complex is dependent on the host proteasome. Together, ICP0 and this triple complex have an additive effect against elevated host immune responses, e.g. under interferon treatment.     Our study elucidates the function of this newly identified tripartite tegument protein complex and reveals a novel way in which herpesviruses antagonise intrinsic and innate immunity.