diff --git a/CHANGES.md b/CHANGES.md
index 9d3ca57..fbf4f24 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,7 @@
+## 1.0.4-SNAPSHOT
+
+* Bug fix: Fix `INDEXED-VALS` invalidly overwriting elements in some transforms involving multiple index changes
+
 ## 1.0.3
 
 * Added `before-index` navigator for inserting a single element into a sequence.
diff --git a/src/clj/com/rpl/specter.cljc b/src/clj/com/rpl/specter.cljc
index f19604d..c9f5feb 100644
--- a/src/clj/com/rpl/specter.cljc
+++ b/src/clj/com/rpl/specter.cljc
@@ -1008,23 +1008,19 @@
         (next-fn [(i/get-cell i) e])
         )))
   (transform* [this structure next-fn]
-    (let [i (i/mutable-cell 0)
-          indices (i/mutable-cell (-> structure count range vec))]
+    (let [indices (i/mutable-cell (-> structure count range))]
       (reduce
        (fn [s e]
-         (let [curri (nth (i/get-cell indices) (i/get-cell i))
+         (let [curri (first (i/get-cell indices))
                [newi newe] (next-fn [curri e])]
-           (if (> newi curri)
-             (i/update-cell! indices
-               (fn [ii]
-                 (loop [j (inc curri)
-                        s ii]
-                   (let [news (update s j dec)]
-                     (if (< j newi)
-                       (recur (inc j) news)
-                       news
-                       ))))))
-           (i/update-cell! i inc)
+           (i/update-cell!
+             indices
+             (fn [ii]
+               (let [ii2 (next ii)]
+                 (if (> newi curri)
+                   (transform [ALL #(>= % (inc curri)) #(<= % newi)] dec ii2)
+                   ii2
+                   ))))
            (->> s
                 (setval (nthpath curri) newe)
                 (setval (index-nav curri) newi)
diff --git a/test/com/rpl/specter/core_test.cljc b/test/com/rpl/specter/core_test.cljc
index 7a253dc..eab7f1a 100644
--- a/test/com/rpl/specter/core_test.cljc
+++ b/test/com/rpl/specter/core_test.cljc
@@ -1624,6 +1624,8 @@
     (is (= [:a :b :e :d :c] (setval [s/INDEXED-VALS s/FIRST] 2 data)))
     (is (= [:b :a :d :c :e] (transform [s/INDEXED-VALS s/FIRST odd?] dec data)))
     (is (= [:a :b :c :d :e] (transform [s/INDEXED-VALS s/FIRST odd?] inc data)))
+    (is (= [0 2 2 4] (transform [s/INDEXED-VALS s/LAST odd?] inc [0 1 2 3])))
+    (is (= [0 1 2 3] (transform [s/INDEXED-VALS (s/collect-one s/LAST) s/FIRST] (fn [i _] i) [2 1 3 0])))
     ))
 
 #?(:clj