  New light scalar particles in the mass range of hundreds of GeV, decaying
into a pair of $W/Z$ bosons can appear in several extensions of the SM. The
focus of collider studies for such a scalar is often on its direct production,
where the scalar is typically only mildly boosted. The observed $W/Z$ are
therefore well-separated, allowing analyses for the scalar resonance in a
standard fashion as a low-mass diboson resonance. In this work we instead focus
on the scenario where the direct production of the scalar is suppressed, and it
is rather produced via the decay of a significantly heavier (a few TeV mass)
new particle, in conjunction with SM particles. Such a process results in the
scalar being highly boosted, rendering the $W/Z$'s from its decay merged. The
final state in such a decay is a "fat" jet, which can be either four-pronged
(for fully hadronic $W/Z$ decays), or may be like a $W/Z$ jet, but with leptons
buried inside (if one of the $W/Z$ decays leptonically). In addition, this fat
jet has a jet mass that can be quite different from that of the $W/Z$/Higgs/top
quark-induced jet, and may be missed by existing searches. In this work, we
develop dedicated algorithms for tagging such multi-layered "boosted dibosons"
at the LHC. As a concrete application, we discuss an extension of the standard
warped extra-dimensional framework where such a light scalar can arise. We
demonstrate that the use of these algorithms gives sensitivity in mass ranges
that are otherwise poorly constrained.
