diff --git a/src/consts.rs b/src/consts.rs
index 7437cc2..a954739 100644
--- a/src/consts.rs
+++ b/src/consts.rs
@@ -20,6 +20,10 @@ pub const SECTOR_BYTES: usize = 2048;
 /// the workspace reads as `sectors * SECTOR_BYTES_U64` with no per-site cast.
 pub const SECTOR_BYTES_U64: u64 = SECTOR_BYTES as u64;
 
+/// Milliseconds per second. For turning a byte count ÷ bytes-per-second into a
+/// movie-time figure (`bytes / bps * MILLIS_PER_SEC`) without a bare `1000.0`.
+pub const MILLIS_PER_SEC: f64 = 1_000.0;
+
 /// Bytes per MPEG-2 transport-stream packet. Common to all MPEG-TS, not just
 /// Blu-ray — prefixed by the format, not a disc type.
 pub const TS_PACKET_BYTES: usize = 188;
diff --git a/src/disc/extract.rs b/src/disc/extract.rs
index ea15a61..1e842d5 100644
--- a/src/disc/extract.rs
+++ b/src/disc/extract.rs
@@ -686,6 +686,7 @@ fn report(opts: &ExtractOptions, done: u64, total: u64) -> bool {
                 bytes_bad_in_main_title: 0,
                 main_title_duration_secs: None,
                 main_title_size_bytes: None,
+                located: Default::default(),
             };
             p.report(&pp)
         }
diff --git a/src/disc/mod.rs b/src/disc/mod.rs
index f753989..e045f27 100644
--- a/src/disc/mod.rs
+++ b/src/disc/mod.rs
@@ -588,6 +588,103 @@ pub fn bytes_bad_in_title(title: &DiscTitle, bad_ranges: &[(u64, u64)]) -> u64 {
     total
 }
 
+/// Byte offset of `lba` within `title`'s extents (concatenated in order), or
+/// `None` if the LBA falls outside every extent. The title is a virtual
+/// contiguous stream; this maps a disc LBA into that stream so a chapter/time
+/// lookup can place it. (Moved from autorip — clients must not re-derive it.)
+fn byte_offset_in_title(lba: u32, title: &DiscTitle) -> Option<u64> {
+    use crate::consts::SECTOR_BYTES_U64;
+    let mut cumulative = 0u64;
+    for ext in &title.extents {
+        if lba >= ext.start_lba && lba < ext.start_lba + ext.sector_count {
+            return Some(cumulative + (lba - ext.start_lba) as u64 * SECTOR_BYTES_U64);
+        }
+        cumulative += ext.sector_count as u64 * SECTOR_BYTES_U64;
+    }
+    None
+}
+
+/// The 1-based chapter + movie-time offset an LBA falls in, or `(None, None)`
+/// if it isn't inside the title.
+fn range_chapter(lba: u32, title: &DiscTitle) -> (Option<u32>, Option<f64>) {
+    if let Some(byte_offset) = byte_offset_in_title(lba, title) {
+        if let Some((ch, t)) = crate::verify::VerifyResult::chapter_at_offset(
+            &title.chapters,
+            byte_offset,
+            title.duration_secs,
+            title.size_bytes,
+        ) {
+            return (Some(ch as u32), Some(t));
+        }
+    }
+    (None, None)
+}
+
+/// Annotate raw bad byte-ranges with chapter + movie time, producing the
+/// rendered drilldown ([`crate::progress::LocatedProgress`]) a client draws.
+/// `raw` is the mapfile's `(byte_pos, byte_len)` set for whichever statuses the
+/// caller cares about (the live "Maybe" set during a patch, or terminal
+/// `Unreadable` for the verdict). The list is sorted largest-movie-time first
+/// and capped at 50; `truncated` reports the overflow. `bps` (title bytes/sec)
+/// is derived from the title so callers don't thread it.
+///
+/// This is the single place range→chapter/time annotation happens; autorip used
+/// to own it and read the mapfile to do so. Now the library computes it from
+/// its in-memory mapfile + title, and the client renders the result verbatim.
+pub fn locate_ranges(raw: &[(u64, u64)], title: &DiscTitle) -> crate::progress::LocatedProgress {
+    use crate::consts::{MILLIS_PER_SEC, SECTOR_BYTES_U64};
+    use crate::progress::{LocatedProgress, LocatedRange};
+    const MAX_LOCATED: usize = 50;
+    let bps = if title.duration_secs > 0.0 {
+        title.size_bytes as f64 / title.duration_secs
+    } else {
+        0.0
+    };
+    let num_ranges = raw.len() as u32;
+    let mut ranges: Vec<LocatedRange> = raw
+        .iter()
+        .map(|(pos, size)| {
+            let lba = pos / SECTOR_BYTES_U64;
+            let count = (size / SECTOR_BYTES_U64) as u32;
+            let duration_ms = if bps > 0.0 {
+                (*size as f64) / bps * MILLIS_PER_SEC
+            } else {
+                0.0
+            };
+            let (chapter, time_offset_secs) = range_chapter(lba as u32, title);
+            LocatedRange {
+                lba,
+                count,
+                duration_ms,
+                chapter,
+                time_offset_secs,
+            }
+        })
+        .collect();
+    ranges.sort_by(|a, b| {
+        b.duration_ms
+            .partial_cmp(&a.duration_ms)
+            .unwrap_or(std::cmp::Ordering::Equal)
+    });
+    let largest_gap_ms = ranges.first().map(|r| r.duration_ms).unwrap_or(0.0);
+    let truncated = ranges.len().saturating_sub(MAX_LOCATED) as u32;
+    ranges.truncate(MAX_LOCATED);
+    // At-risk movie time = duration of the ranges that intersect the title
+    // extents (the others are menus/extras → no movie impact).
+    let main_at_risk_ms = if bps > 0.0 {
+        bytes_bad_in_title(title, raw) as f64 * MILLIS_PER_SEC / bps
+    } else {
+        0.0
+    };
+    LocatedProgress {
+        ranges,
+        num_ranges,
+        truncated,
+        main_at_risk_ms,
+        largest_gap_ms,
+    }
+}
+
 // ─── Display helpers ────────────────────────────────────────────────────────
 
 impl Codec {
@@ -3512,6 +3609,15 @@ impl Disc {
                         bytes_bad_in_main_title: main_title_bad,
                         main_title_duration_secs: main_title.map(|t| t.duration_secs),
                         main_title_size_bytes: main_title.map(|t| t.size_bytes),
+                        // Rendered drilldown from the consumer's in-memory
+                        // snapshot (bad ranges) + title; empty until the first
+                        // snapshot arrives.
+                        located: match &cached_snapshot {
+                            Some(snap) => main_title
+                                .map(|t| locate_ranges(&snap.bad_ranges, t))
+                                .unwrap_or_default(),
+                            None => crate::progress::LocatedProgress::default(),
+                        },
                     };
                     if !reporter.report(&pp) {
                         halt_requested = true;
diff --git a/src/disc/patch.rs b/src/disc/patch.rs
index a2cb561..7146ed2 100644
--- a/src/disc/patch.rs
+++ b/src/disc/patch.rs
@@ -2124,6 +2124,12 @@ impl Disc {
             bytes_bad_in_main_title: main_title_bad,
             main_title_duration_secs: main_title.map(|t| t.duration_secs),
             main_title_size_bytes: main_title.map(|t| t.size_bytes),
+            // The rendered drilldown — located ranges + at-risk movie time —
+            // computed here from the in-memory bad-range set + title so the
+            // client renders it verbatim and never reads the mapfile.
+            located: main_title
+                .map(|t| crate::disc::locate_ranges(&bad_ranges_now, t))
+                .unwrap_or_default(),
         };
         !reporter.report(&pp)
     }
diff --git a/src/progress.rs b/src/progress.rs
index fad4f7d..f1e6b23 100644
--- a/src/progress.rs
+++ b/src/progress.rs
@@ -35,6 +35,51 @@ pub enum PassKind {
     Verify,
 }
 
+/// One located bad/not-yet-good range, annotated with the chapter and movie
+/// time it falls in. This is the *rendered* drilldown a client draws: the LBA
+/// and sector count place it on the disc map, while `chapter` and
+/// `time_offset_secs` tell the user *what* is affected. Computed by the library
+/// (which owns the mapfile and title) so no client ever re-derives it. If the
+/// mapfile becomes a mapdb, this type and its producer change; clients don't.
+#[derive(Debug, Clone)]
+pub struct LocatedRange {
+    /// First sector (LBA) of the range.
+    pub lba: u64,
+    /// Length of the range in sectors.
+    pub count: u32,
+    /// Movie time this range spans, in milliseconds (range bytes ÷ title
+    /// bytes/sec). Used to sort the drilldown and size the "largest gap".
+    pub duration_ms: f64,
+    /// 1-based chapter the range falls in, if it lands inside the title.
+    pub chapter: Option<u32>,
+    /// Movie time offset (seconds) where the range begins, if in-title.
+    pub time_offset_secs: Option<f64>,
+}
+
+/// The fully-rendered "where is the damage" view for one progress sample: the
+/// located drilldown plus the derived movie-time figures. A client maps this
+/// straight to its UI — it never touches the mapfile. `Default` is the empty
+/// (no-damage / not-applicable) view, used by phases that don't locate ranges
+/// (verify, extract, mux-label).
+#[derive(Debug, Clone, Default)]
+pub struct LocatedProgress {
+    /// Located not-yet-good ranges, largest-movie-time first, capped (see
+    /// `truncated`).
+    pub ranges: Vec<LocatedRange>,
+    /// Total number of located ranges before the cap (so a client can say
+    /// "N sections").
+    pub num_ranges: u32,
+    /// How many ranges were dropped by the display cap (`ranges.len()` is the
+    /// kept count; this is the "+X more").
+    pub truncated: u32,
+    /// Main-feature movie time still at risk: duration of the not-yet-good
+    /// ranges that intersect the title extents, in milliseconds. `0` when all
+    /// damage is out-of-feature (menus/extras).
+    pub main_at_risk_ms: f64,
+    /// Movie time of the single largest range, in milliseconds.
+    pub largest_gap_ms: f64,
+}
+
 /// One progress sample from a pipeline phase.
 ///
 /// `work_done / work_total` is the per-pass percentage — always 0..=100%
@@ -48,7 +93,12 @@ pub enum PassKind {
 /// - `bytes_good_total` = good + slow + recovered sectors × 2048
 /// - `bytes_unreadable_total` = bad sectors × 2048
 /// - `bytes_pending_total` = 0 (verify processes sequentially, nothing pending)
-#[derive(Debug, Clone, Copy)]
+///
+/// NOT `Copy`: `located` carries a `Vec`. Constructed once per (throttled)
+/// emission and passed by reference to `Progress::report`, so this costs one
+/// small heap alloc per UI tick — cheap, and it makes `PassProgress` the single
+/// complete contract a client renders from.
+#[derive(Debug, Clone)]
 pub struct PassProgress {
     pub kind: PassKind,
     pub work_done: u64,
@@ -72,6 +122,11 @@ pub struct PassProgress {
     pub main_title_duration_secs: Option<f64>,
     /// Main title size in bytes (sum of extent sizes).
     pub main_title_size_bytes: Option<u64>,
+    /// The fully-rendered "where is the damage" drilldown for this sample:
+    /// located ranges + at-risk movie time. Empty (`Default`) for phases that
+    /// don't locate ranges. A client renders the disc map + section list from
+    /// this and NEVER reads the mapfile itself.
+    pub located: LocatedProgress,
 }
 
 impl PassProgress {
diff --git a/src/verify.rs b/src/verify.rs
index b22f1bc..27ae23d 100644
--- a/src/verify.rs
+++ b/src/verify.rs
@@ -221,6 +221,7 @@ pub fn verify_title(
                         bytes_bad_in_main_title: 0,
                         main_title_duration_secs: Some(title.duration_secs),
                         main_title_size_bytes: Some(total_sectors * 2048),
+                        located: Default::default(),
                     };
                     if !cb.report(&pp) {
                         break 'outer;
@@ -271,6 +272,7 @@ pub fn verify_title(
                                     bytes_bad_in_main_title: 0,
                                     main_title_duration_secs: Some(title.duration_secs),
                                     main_title_size_bytes: Some(total_sectors * 2048),
+                                    located: Default::default(),
                                 })
                             })
                         });
@@ -335,6 +337,7 @@ pub fn verify_title(
                             bytes_bad_in_main_title: 0,
                             main_title_duration_secs: Some(title.duration_secs),
                             main_title_size_bytes: Some(total_sectors * 2048),
+                            located: Default::default(),
                         };
                         if !cb.report(&pp) {
                             break 'outer;