diff --git a/ext/BrillouinPlotlyJSExt/dispersion.jl b/ext/BrillouinPlotlyJSExt/dispersion.jl
index dbb1e0a..400a810 100644
--- a/ext/BrillouinPlotlyJSExt/dispersion.jl
+++ b/ext/BrillouinPlotlyJSExt/dispersion.jl
@@ -18,6 +18,77 @@ const DEFAULT_PLOTLY_LAYOUT_DISPERSION = Layout(
     plot_bgcolor=TRANSPARENT_COL[], paper_bgcolor=TRANSPARENT_COL[],
     )
 
+
+function plot(kpi::KPathInterpolant, traces::Vector{<:AbstractTrace},
+              layout::Layout = Layout();
+              ylims = nothing, ylabel = nothing, title = nothing,
+              config::PlotConfig = PlotConfig(responsive=true, displaylogo=false))
+
+    # merge (and implicitly copy) `layout` (copy ensures we can mutate `layout` without
+    # corrupting user input)
+    layout = merge(DEFAULT_PLOTLY_LAYOUT_DISPERSION, layout)
+
+    # set default y-limits in layout, if not already set
+    yaxis = get!(layout.fields, :yaxis, attr())
+    if isnothing(ylims)
+        if !haskey(yaxis, :range)
+            yaxis[:range] = ylims
+        else
+            ylims = yaxis[:range] # grab what was already in `layout`
+        end
+    else
+        # overwrite if ylims was provided, regardless of what it is in `layout`
+        yaxis[:range] = ylims
+    end
+    yaxis[:title] = ylabel
+
+    # add title, if requested
+    if !isnothing(title)
+        if title isa String
+            layout[:title] = attr(text=title)
+        else
+            layout[:title] = title
+        end
+    end
+
+    # prepare to plot band diagram
+    Npaths           = length(kpi.kpaths)
+    local_xs         = cumdists.(cartesianize(kpi).kpaths)
+    local_xs_lengths = last.(local_xs)
+    total_xs_lengths = sum(local_xs_lengths)
+    spacing          = total_xs_lengths / 30
+    rel_xs_lengths   = local_xs_lengths./(total_xs_lengths+spacing*(Npaths-1))
+    rel_spacing      = spacing/(total_xs_lengths+spacing*(Npaths-1))
+
+    # plot k-lines/labels
+    xticks = [Vector{Float64}(undef, length(labels)) for labels in kpi.labels]
+    xlabs  = [Vector{Symbol}(undef, length(labels)) for labels in kpi.labels]
+    domain_start = 0.0 # subplot domain "start" point
+    for (path_idx, (local_x, labels)) in enumerate(zip(local_xs, kpi.labels))
+        # define xticks
+        for (lab_idx, (x_idx, lab)) in enumerate(labels)
+            xticks[path_idx][lab_idx] = local_x[x_idx]
+            xlabs[path_idx][lab_idx]  = lab
+        end
+
+        # set subplot sizes and local xticks & xrange
+        sym_xaxis = Symbol("xaxis$path_idx") # subplot xaxis name
+
+        layout[sym_xaxis] = copy(get(layout, :xaxis, attr()))
+        layout[sym_xaxis][:range] = [extrema(local_x)...]
+        layout[sym_xaxis][:tickvals] = xticks[path_idx]
+        layout[sym_xaxis][:ticktext] = xlabs[path_idx]
+
+        domain_end = domain_start + rel_xs_lengths[path_idx]
+        layout[Symbol(sym_xaxis, "_domain")] = [domain_start, domain_end]
+        domain_start = domain_end + rel_spacing
+    end
+    delete!(layout.fields, :xaxis) # get rid of unused xaxis in layout; causes artifacts...
+
+    return plot(traces, layout; config=config)
+end
+
+
 """
     plot(kpi::KPathInterpolant, bands, [layout]; kwargs...)
 
@@ -63,73 +134,33 @@ Alternatively, some simple settings can be set directly via keyword arguments (s
 """
 function plot(kpi::KPathInterpolant, bands,
               layout::Layout = Layout();
-              ylims = nothing, ylabel = "Energy", title = nothing,
+              ylims = default_dispersion_ylims(bands), ylabel = "Energy",
               band_highlights::Union{Dict, Nothing} = nothing,
               annotations::Union{Dict, Nothing} = nothing,
-              config::PlotConfig = PlotConfig(responsive=true, displaylogo=false))
+              kwargs...)
     # check input
     N = length(kpi)
     if !all(band -> length(band) == N, bands)
         throw(DimensionMismatch("mismatched dimensions of `kpi` and `bands`"))
     end
-    # merge (and implicitly copy) `layout` (copy ensures we can mutate `layout` without
-    # corrupting user input)
-    layout = merge(DEFAULT_PLOTLY_LAYOUT_DISPERSION, layout)
-
-    # set default y-limits in layout, if not already set
-    yaxis = get!(layout.fields, :yaxis, attr())
-    if isnothing(ylims)
-        if !haskey(yaxis, :range)
-            ylims = default_dispersion_ylims(bands)
-            yaxis[:range] = ylims
-        else
-            ylims = yaxis[:range] # grab what was already in `layout`
-        end
-    else
-        # overwrite if ylims was provided, regardless of what it is in `layout`
-        yaxis[:range] = ylims
-    end
-    yaxis[:title] = ylabel
-
-    # add title, if requested
-    if !isnothing(title)
-        if title isa String
-            layout[:title] = attr(text=title)
-        else
-            layout[:title] = title
-        end
-    end
 
     # prepare to plot band diagram
-    Npaths           = length(kpi.kpaths)
     local_xs         = cumdists.(cartesianize(kpi).kpaths)
-    local_xs_lengths = last.(local_xs)
-    total_xs_lengths = sum(local_xs_lengths)
-    spacing          = total_xs_lengths / 30
-    rel_xs_lengths   = local_xs_lengths./(total_xs_lengths+spacing*(Npaths-1))
-    rel_spacing      = spacing/(total_xs_lengths+spacing*(Npaths-1))
 
     # plot bands and k-lines/labels
     tbands = Vector{GenericTrace{Dict{Symbol,Any}}}()
-    xticks = [Vector{Float64}(undef, length(labels)) for labels in kpi.labels]
-    xlabs  = [Vector{Symbol}(undef, length(labels)) for labels in kpi.labels]
     start_idx = 1
-    domain_start = 0.0 # subplot domain "start" point
     for (path_idx, (local_x, labels)) in enumerate(zip(local_xs, kpi.labels))
         stop_idx = start_idx+length(local_x)-1
         # plot bands
         for (i, band) in enumerate(bands)
-            line = something(_get_value_if_in_ranges(band_highlights, i), 
-                             attr(color=BAND_COL[], width=3)) # default            
+            line = something(_get_value_if_in_ranges(band_highlights, i),
+                             attr(color=BAND_COL[], width=3)) # default
             push!(tbands,
                 PlotlyJS.scatter(x=local_x, y=band[start_idx:stop_idx],
                     hoverinfo="y", mode="lines", line=line, xaxis="x$path_idx", yaxis="y"))
         end
-        # define xticks
-        for (lab_idx, (x_idx, lab)) in enumerate(labels)
-            xticks[path_idx][lab_idx] = local_x[x_idx]
-            xlabs[path_idx][lab_idx]  = lab
-        end
+
         # place any high-symmetry point annotations
         if annotations !== nothing
             for (lab, positions_and_strs) in annotations
@@ -157,25 +188,12 @@ function plot(kpi::KPathInterpolant, bands,
                 end
             end
         end
-        
-        # set subplot sizes and local xticks & xrange
-        sym_xaxis = Symbol("xaxis$path_idx") # subplot xaxis name
-
-        layout[sym_xaxis] = copy(get(layout, :xaxis, attr()))
-        layout[sym_xaxis][:range] = [extrema(local_x)...]
-        layout[sym_xaxis][:tickvals] = xticks[path_idx]
-        layout[sym_xaxis][:ticktext] = xlabs[path_idx]
-        
-        domain_end = domain_start + rel_xs_lengths[path_idx]
-        layout[Symbol(sym_xaxis, "_domain")] = [domain_start, domain_end]
-        domain_start = domain_end + rel_spacing
 
         # prepare for next iteration
         start_idx = stop_idx + 1
     end
-    delete!(layout.fields, :xaxis) # get rid of unused xaxis in layout; causes artifacts...
 
-    return plot(tbands, layout; config=config)
+    return plot(kpi, tbands, layout; ylims=ylims, ylabel=ylabel, kwargs...)
 end
 # `bands` can also be supplied as a matrix (w/ distinct bands in distinct columns)
 function plot(kpi::KPathInterpolant, bands::AbstractMatrix{<:Real},
@@ -188,7 +206,7 @@ function plot(kpi::KPathInterpolant, bands::AbstractMatrix{<:Real},
 end
 
 function default_dispersion_ylims(bands)
-    ylims = [mapfoldl(minimum, min, bands, init=Inf), 
+    ylims = [mapfoldl(minimum, min, bands, init=Inf),
              mapfoldl(maximum, max, bands, init=-Inf)]
     δ = (ylims[2]-ylims[1])/30
     if isapprox(ylims[1], 0, atol=1e-6)
@@ -205,4 +223,63 @@ function _get_value_if_in_ranges(d::Dict, i::Integer)
     end
     return nothing
 end
-_get_value_if_in_ranges(::Nothing, ::Integer) = nothing
\ No newline at end of file
+_get_value_if_in_ranges(::Nothing, ::Integer) = nothing
+
+# ---------------------------------------------------------------------------------------- #
+
+"""
+    plot(kpi::KPathInterpolant, ωs, fields, [layout]; kwargs...)
+
+Plot a dispersion heatmap for provided `fields` and **k**-path interpolant `kpi`.
+
+`fields` must be an iterable of real matrices (e.g., a `Vector{Matrix{Float64}}`),
+with the first iteration running over distinct fields to overlay.
+Note that the size of each iterant of `fields` must equal `(length(kpi), length(ωs))`.
+
+## Keyword arguments `kwargs`
+
+- `ylims`: y-axis limits (default: `extrema(ωs)`)
+
+- `ylabel`: y-axis label (default: "Energy")
+
+- `title`: plot title (default: `nothing`); can be a `String` or an `attr` dictionary of
+  PlotlyJS properties
+
+- `opacity`: transparency of colormap (default: `1`); useful to set a value less than one
+  when overlaying multiple `fields`
+
+- `colorscale`: an iteratable of PlotlyJS color scales (default: ["YlGnBu"])
+
+- `reversescale`: boolean that reverses color scale (default: false)
+"""
+function plot(kpi::KPathInterpolant, ωs, fields,
+              layout::Layout = Layout();
+              ylims = extrema(ωs), ylabel = "Energy",
+              opacity=1, colorscale=["YlGnBu"], reversescale=false,
+              kwargs...)
+    # check input
+    N = length(kpi); M = length(ωs)
+    if !all(field -> size(field) == (N,M), fields)
+        throw(DimensionMismatch("mismatched dimensions of `kpi` with `ωs` and `fields`"))
+    end
+
+    # prepare to plot band diagram
+    local_xs         = cumdists.(cartesianize(kpi).kpaths)
+
+    # plot bands and k-lines/labels
+    heatmaps = Vector{GenericTrace{Dict{Symbol,Any}}}()
+    start_idx = 1
+    for (path_idx, (local_x, labels)) in enumerate(zip(local_xs, kpi.labels))
+        stop_idx = start_idx+length(local_x)-1
+        # plot fields
+        for (i, field) in enumerate(fields)
+            push!(heatmaps,
+                PlotlyJS.heatmap(x=local_x, y=ωs, z=transpose(field[start_idx:stop_idx,:]),
+                xaxis="x$path_idx", yaxis="y", opacity=opacity,
+                colorscale=colorscale[mod(i-1,length(colorscale))+1], reversescale=reversescale))
+        end
+        start_idx = stop_idx + 1
+    end
+
+    plot(kpi, heatmaps, layout; ylims=ylims, ylabel=ylabel, kwargs...)
+end