diff --git a/db_stress_tool/db_stress_shared_state.h b/db_stress_tool/db_stress_shared_state.h
index 4e61d2252..c53a0742b 100644
--- a/db_stress_tool/db_stress_shared_state.h
+++ b/db_stress_tool/db_stress_shared_state.h
@@ -215,6 +215,32 @@ class SharedState {
     }
   }
 
+  // Returns a collection of mutex locks covering the key range [start, end) in
+  // `cf`.
+  std::vector<std::unique_ptr<MutexLock>> GetLocksForKeyRange(int cf,
+                                                              int64_t start,
+                                                              int64_t end) {
+    std::vector<std::unique_ptr<MutexLock>> range_locks;
+
+    if (start >= end) {
+      return range_locks;
+    }
+
+    const int64_t start_idx = start >> log2_keys_per_lock_;
+
+    int64_t end_idx = end >> log2_keys_per_lock_;
+    if ((end & ((1 << log2_keys_per_lock_) - 1)) == 0) {
+      --end_idx;
+    }
+
+    for (int64_t idx = start_idx; idx <= end_idx; ++idx) {
+      range_locks.emplace_back(
+          std::make_unique<MutexLock>(&key_locks_[cf][idx]));
+    }
+
+    return range_locks;
+  }
+
   Status SaveAtAndAfter(DB* db) {
     return expected_state_manager_->SaveAtAndAfter(db);
   }
diff --git a/db_stress_tool/no_batched_ops_stress.cc b/db_stress_tool/no_batched_ops_stress.cc
index 533d0b95c..031134a0c 100644
--- a/db_stress_tool/no_batched_ops_stress.cc
+++ b/db_stress_tool/no_batched_ops_stress.cc
@@ -1127,33 +1127,41 @@ class NonBatchedOpsStressTest : public StressTest {
       ThreadState* thread, const ReadOptions& read_opts,
       const std::vector<int>& rand_column_families,
       const std::vector<int64_t>& rand_keys) override {
-    // Lock the whole range over which we might iterate to ensure it doesn't
-    // change under us.
-    std::vector<std::unique_ptr<MutexLock>> range_locks;
-    int64_t lb = rand_keys[0];
-    int rand_column_family = rand_column_families[0];
+    assert(thread);
+    assert(!rand_column_families.empty());
+    assert(!rand_keys.empty());
+
     auto shared = thread->shared;
+    assert(shared);
+
     int64_t max_key = shared->GetMaxKey();
-    if (static_cast<uint64_t>(lb) > max_key - FLAGS_num_iterations) {
-      lb = thread->rand.Next() % (max_key - FLAGS_num_iterations + 1);
-    }
-    for (int j = 0; j < static_cast<int>(FLAGS_num_iterations); ++j) {
-      if (j == 0 || ((lb + j) & ((1 << FLAGS_log2_keys_per_lock) - 1)) == 0) {
-        range_locks.emplace_back(
-            new MutexLock(shared->GetMutexForKey(rand_column_family, lb + j)));
-      }
+
+    const int64_t num_iter = static_cast<int64_t>(FLAGS_num_iterations);
+
+    int64_t lb = rand_keys[0];
+    if (lb > max_key - num_iter) {
+      lb = thread->rand.Next() % (max_key - num_iter + 1);
     }
-    int64_t ub = lb + FLAGS_num_iterations;
-    // Locks acquired for [lb, ub)
-    ReadOptions readoptscopy(read_opts);
+
+    const int64_t ub = lb + num_iter;
+
+    // Lock the whole range over which we might iterate to ensure it doesn't
+    // change under us.
+    const int rand_column_family = rand_column_families[0];
+    std::vector<std::unique_ptr<MutexLock>> range_locks =
+        shared->GetLocksForKeyRange(rand_column_family, lb, ub);
+
+    ReadOptions ro(read_opts);
+    ro.total_order_seek = true;
+
     std::string read_ts_str;
     Slice read_ts;
     if (FLAGS_user_timestamp_size > 0) {
       read_ts_str = GetNowNanos();
       read_ts = read_ts_str;
-      readoptscopy.timestamp = &read_ts;
+      ro.timestamp = &read_ts;
     }
-    readoptscopy.total_order_seek = true;
+
     std::string max_key_str;
     Slice max_key_slice;
     if (!FLAGS_destroy_db_initially) {
@@ -1162,11 +1170,41 @@ class NonBatchedOpsStressTest : public StressTest {
       // to restrict iterator from reading keys written in batched_op_stress
       // that do not have expected state updated and may not be parseable by
       // GetIntVal().
-      readoptscopy.iterate_upper_bound = &max_key_slice;
+      ro.iterate_upper_bound = &max_key_slice;
     }
-    auto cfh = column_families_[rand_column_family];
+
+    ColumnFamilyHandle* const cfh = column_families_[rand_column_family];
+    assert(cfh);
+
+    std::unique_ptr<Iterator> iter(db_->NewIterator(ro, cfh));
+
     std::string op_logs;
-    std::unique_ptr<Iterator> iter(db_->NewIterator(readoptscopy, cfh));
+
+    auto check_columns = [&]() {
+      assert(iter);
+      assert(iter->Valid());
+
+      const WideColumns expected_columns = GenerateExpectedWideColumns(
+          GetValueBase(iter->value()), iter->value());
+      if (iter->columns() != expected_columns) {
+        shared->SetVerificationFailure();
+
+        fprintf(stderr,
+                "Verification failed for key %s: "
+                "Value and columns inconsistent: %s\n",
+                Slice(iter->key()).ToString(/* hex */ true).c_str(),
+                DebugString(iter->value(), iter->columns(), expected_columns)
+                    .c_str());
+        fprintf(stderr, "Column family: %s, op_logs: %s\n",
+                cfh->GetName().c_str(), op_logs.c_str());
+
+        thread->stats.AddErrors(1);
+
+        return false;
+      }
+
+      return true;
+    };
 
     auto check_no_key_in_range = [&](int64_t start, int64_t end) {
       for (auto j = std::max(start, lb); j < std::min(end, ub); ++j) {
@@ -1198,10 +1236,13 @@ class NonBatchedOpsStressTest : public StressTest {
     // The random sequence Next and Prev test below tends to be very short
     // ranged.
     int64_t last_key = lb - 1;
+
     std::string key_str = Key(lb);
-    iter->Seek(Slice(key_str));
+    iter->Seek(key_str);
+
     op_logs += "S " + Slice(key_str).ToString(true) + " ";
-    uint64_t curr;
+
+    uint64_t curr = 0;
     while (true) {
       if (!iter->Valid()) {
         if (!iter->status().ok()) {
@@ -1213,29 +1254,38 @@ class NonBatchedOpsStressTest : public StressTest {
           thread->stats.AddErrors(1);
           return iter->status();
         }
-        if (!check_no_key_in_range(last_key + 1, static_cast<int64_t>(ub))) {
-          // error reported in check_no_key_in_range()
+        if (!check_no_key_in_range(last_key + 1, ub)) {
           return Status::OK();
         }
         break;
       }
+
+      if (!check_columns()) {
+        return Status::OK();
+      }
+
       // iter is valid, the range (last_key, current key) was skipped
       GetIntVal(iter->key().ToString(), &curr);
       if (!check_no_key_in_range(last_key + 1, static_cast<int64_t>(curr))) {
         return Status::OK();
       }
+
       last_key = static_cast<int64_t>(curr);
       if (last_key >= ub - 1) {
         break;
       }
+
       iter->Next();
+
       op_logs += "N";
     }
 
     // backward scan
     key_str = Key(ub - 1);
-    iter->SeekForPrev(Slice(key_str));
+    iter->SeekForPrev(key_str);
+
     op_logs += " SFP " + Slice(key_str).ToString(true) + " ";
+
     last_key = ub;
     while (true) {
       if (!iter->Valid()) {
@@ -1253,16 +1303,24 @@ class NonBatchedOpsStressTest : public StressTest {
         }
         break;
       }
+
+      if (!check_columns()) {
+        return Status::OK();
+      }
+
       // the range (current key, last key) was skipped
       GetIntVal(iter->key().ToString(), &curr);
       if (!check_no_key_in_range(static_cast<int64_t>(curr + 1), last_key)) {
         return Status::OK();
       }
+
       last_key = static_cast<int64_t>(curr);
       if (last_key <= lb) {
         break;
       }
+
       iter->Prev();
+
       op_logs += "P";
     }
 
@@ -1271,11 +1329,14 @@ class NonBatchedOpsStressTest : public StressTest {
       // change. It is safe to refresh since the testing key range is locked.
       iter->Refresh();
     }
+
     // start from middle of [lb, ub) otherwise it is easy to iterate out of
     // locked range
-    int64_t mid = lb + static_cast<int64_t>(FLAGS_num_iterations / 2);
+    const int64_t mid = lb + num_iter / 2;
+
     key_str = Key(mid);
-    Slice key = key_str;
+    const Slice key(key_str);
+
     if (thread->rand.OneIn(2)) {
       iter->Seek(key);
       op_logs += " S " + key.ToString(true) + " ";
@@ -1295,16 +1356,20 @@ class NonBatchedOpsStressTest : public StressTest {
       }
     }
 
-    for (uint64_t i = 0; i < FLAGS_num_iterations && iter->Valid(); i++) {
+    for (int64_t i = 0; i < num_iter && iter->Valid(); ++i) {
+      if (!check_columns()) {
+        return Status::OK();
+      }
+
       GetIntVal(iter->key().ToString(), &curr);
-      if (curr < static_cast<uint64_t>(lb)) {
+      if (static_cast<int64_t>(curr) < lb) {
         iter->Next();
         op_logs += "N";
-      } else if (curr >= static_cast<uint64_t>(ub)) {
+      } else if (static_cast<int64_t>(curr) >= ub) {
         iter->Prev();
         op_logs += "P";
       } else {
-        uint32_t expected_value =
+        const uint32_t expected_value =
             shared->Get(rand_column_family, static_cast<int64_t>(curr));
         if (expected_value == shared->DELETION_SENTINEL) {
           // Fail fast to preserve the DB state.
@@ -1316,13 +1381,14 @@ class NonBatchedOpsStressTest : public StressTest {
           thread->stats.AddErrors(1);
           break;
         }
+
         if (thread->rand.OneIn(2)) {
           iter->Next();
           op_logs += "N";
           if (!iter->Valid()) {
             break;
           }
-          uint64_t next;
+          uint64_t next = 0;
           GetIntVal(iter->key().ToString(), &next);
           if (!check_no_key_in_range(static_cast<int64_t>(curr + 1),
                                      static_cast<int64_t>(next))) {
@@ -1334,7 +1400,7 @@ class NonBatchedOpsStressTest : public StressTest {
           if (!iter->Valid()) {
             break;
           }
-          uint64_t prev;
+          uint64_t prev = 0;
           GetIntVal(iter->key().ToString(), &prev);
           if (!check_no_key_in_range(static_cast<int64_t>(prev + 1),
                                      static_cast<int64_t>(curr))) {
@@ -1343,6 +1409,7 @@ class NonBatchedOpsStressTest : public StressTest {
         }
       }
     }
+
     if (!iter->status().ok()) {
       thread->shared->SetVerificationFailure();
       fprintf(stderr, "TestIterate against expected state error: %s\n",
@@ -1352,7 +1419,9 @@ class NonBatchedOpsStressTest : public StressTest {
       thread->stats.AddErrors(1);
       return iter->status();
     }
+
     thread->stats.AddIterations(1);
+
     return Status::OK();
   }