diff --git a/src/column.js b/src/column.js
index 4b1dbcb..e7b8592 100644
--- a/src/column.js
+++ b/src/column.js
@@ -64,7 +64,7 @@ export function readColumn(reader, rowGroup, columnMetadata, schemaPath, { compr
         // wrap nested flat data by depth
         for (let i = 2; i < schemaPath.length; i++) {
           if (schemaPath[i].element.repetition_type !== 'REQUIRED') {
-            values = [values]
+            values = Array.from(values, e => [e])
           }
         }
       }
diff --git a/test/files/duckdb3734.json b/test/files/duckdb3734.json
new file mode 100644
index 0000000..f27184c
--- /dev/null
+++ b/test/files/duckdb3734.json
@@ -0,0 +1,102 @@
+[
+  [
+    "tt0000001",
+    {
+      "category": "self",
+      "characters": ["[\"Self\"]"],
+      "job": "\\N",
+      "nconst": "nm1588970",
+      "ordering": 1
+    }
+  ],
+  [
+    "tt0000001",
+    {
+      "category": "director",
+      "characters": ["\\N"],
+      "job": "\\N",
+      "nconst": "nm0005690",
+      "ordering": 2
+    }
+  ],
+  [
+    "tt0000001",
+    {
+      "category": "cinematographer",
+      "characters": ["\\N"],
+      "job": "director of photography",
+      "nconst": "nm0374658",
+      "ordering": 3
+    }
+  ],
+  [
+    "tt0000002",
+    {
+      "category": "director",
+      "characters": ["\\N"],
+      "job": "\\N",
+      "nconst": "nm0721526",
+      "ordering": 1
+    }
+  ],
+  [
+    "tt0000002",
+    {
+      "category": "composer",
+      "characters": ["\\N"],
+      "job": "\\N",
+      "nconst": "nm1335271",
+      "ordering": 2
+    }
+  ],
+  [
+    "tt0000003",
+    {
+      "category": "director",
+      "characters": ["\\N"],
+      "job": "\\N",
+      "nconst": "nm0721526",
+      "ordering": 1
+    }
+  ],
+  [
+    "tt0000003",
+    {
+      "category": "producer",
+      "characters": ["\\N"],
+      "job": "producer",
+      "nconst": "nm1770680",
+      "ordering": 2
+    }
+  ],
+  [
+    "tt0000003",
+    {
+      "category": "composer",
+      "characters": ["\\N"],
+      "job": "\\N",
+      "nconst": "nm1335271",
+      "ordering": 3
+    }
+  ],
+  [
+    "tt0000003",
+    {
+      "category": "editor",
+      "characters": ["\\N"],
+      "job": "\\N",
+      "nconst": "nm5442200",
+      "ordering": 4
+    }
+  ],
+  [
+    "tt0000004",
+    {
+      "category": "director",
+      "characters": ["\\N"],
+      "job": "\\N",
+      "nconst": "nm0721526",
+      "ordering": 1
+    }
+  ]
+]
diff --git a/test/files/duckdb3734.metadata.json b/test/files/duckdb3734.metadata.json
new file mode 100644
index 0000000..bfaa7e9
--- /dev/null
+++ b/test/files/duckdb3734.metadata.json
@@ -0,0 +1,231 @@
+{
+ "version": 1,
+ "schema": [
+   {
+     "repetition_type": "REQUIRED",
+     "name": "duckdb_schema",
+     "num_children": 2
+   },
+   {
+     "type": "BYTE_ARRAY",
+     "repetition_type": "OPTIONAL",
+     "name": "tconst",
+     "num_children": 0,
+     "converted_type": "UTF8"
+   },
+   {
+     "repetition_type": "OPTIONAL",
+     "name": "principals",
+     "num_children": 5
+   },
+   {
+     "type": "INT32",
+     "repetition_type": "OPTIONAL",
+     "name": "ordering",
+     "num_children": 0,
+     "converted_type": "INT_32"
+   },
+   {
+     "type": "BYTE_ARRAY",
+     "repetition_type": "OPTIONAL",
+     "name": "nconst",
+     "num_children": 0,
+     "converted_type": "UTF8"
+   },
+   {
+     "type": "BYTE_ARRAY",
+     "repetition_type": "OPTIONAL",
+     "name": "category",
+     "num_children": 0,
+     "converted_type": "UTF8"
+   },
+   {
+     "type": "BYTE_ARRAY",
+     "repetition_type": "OPTIONAL",
+     "name": "job",
+     "num_children": 0,
+     "converted_type": "UTF8"
+   },
+   {
+     "repetition_type": "OPTIONAL",
+     "name": "characters",
+     "num_children": 1,
+     "converted_type": "LIST"
+   },
+   {
+     "repetition_type": "REPEATED",
+     "name": "list",
+     "num_children": 1
+   },
+   {
+     "type": "BYTE_ARRAY",
+     "repetition_type": "OPTIONAL",
+     "name": "element",
+     "num_children": 0,
+     "converted_type": "UTF8"
+   }
+ ],
+ "num_rows": 10,
+ "row_groups": [
+   {
+     "columns": [
+       {
+         "file_offset": 0,
+         "meta_data": {
+           "type": "BYTE_ARRAY",
+           "encodings": [
+             "PLAIN",
+             "RLE_DICTIONARY"
+           ],
+           "path_in_schema": [
+             "tconst"
+           ],
+           "codec": "SNAPPY",
+           "num_values": 10,
+           "total_uncompressed_size": 0,
+           "total_compressed_size": 83,
+           "data_page_offset": 4,
+           "statistics": {
+             "max": "tt0000004",
+             "min": "tt0000001",
+             "null_count": 0,
+             "max_value": "tt0000004",
+             "min_value": "tt0000001"
+           }
+         }
+       },
+       {
+         "file_offset": 0,
+         "meta_data": {
+           "type": "INT32",
+           "encodings": [
+             "PLAIN"
+           ],
+           "path_in_schema": [
+             "principals",
+             "ordering"
+           ],
+           "codec": "SNAPPY",
+           "num_values": 10,
+           "total_uncompressed_size": 0,
+           "total_compressed_size": 53,
+           "data_page_offset": 87,
+           "statistics": {
+             "max": 4,
+             "min": 1,
+             "null_count": 0,
+             "max_value": 4,
+             "min_value": 1
+           }
+         }
+       },
+       {
+         "file_offset": 0,
+         "meta_data": {
+           "type": "BYTE_ARRAY",
+           "encodings": [
+             "PLAIN"
+           ],
+           "path_in_schema": [
+             "principals",
+             "nconst"
+           ],
+           "codec": "SNAPPY",
+           "num_values": 10,
+           "total_uncompressed_size": 0,
+           "total_compressed_size": 116,
+           "data_page_offset": 140,
+           "statistics": {
+             "max": "nm5442200",
+             "min": "nm0005690",
+             "null_count": 0,
+             "max_value": "nm5442200",
+             "min_value": "nm0005690"
+           }
+         }
+       },
+       {
+         "file_offset": 0,
+         "meta_data": {
+           "type": "BYTE_ARRAY",
+           "encodings": [
+             "PLAIN"
+           ],
+           "path_in_schema": [
+             "principals",
+             "category"
+           ],
+           "codec": "SNAPPY",
+           "num_values": 10,
+           "total_uncompressed_size": 0,
+           "total_compressed_size": 121,
+           "data_page_offset": 256,
+           "statistics": {
+             "max": "self",
+             "min": "cinematographer",
+             "null_count": 0,
+             "max_value": "self",
+             "min_value": "cinematographer"
+           }
+         }
+       },
+       {
+         "file_offset": 0,
+         "meta_data": {
+           "type": "BYTE_ARRAY",
+           "encodings": [
+             "PLAIN"
+           ],
+           "path_in_schema": [
+             "principals",
+             "job"
+           ],
+           "codec": "SNAPPY",
+           "num_values": 10,
+           "total_uncompressed_size": 0,
+           "total_compressed_size": 90,
+           "data_page_offset": 377,
+           "statistics": {
+             "max": "producer",
+             "min": "\\N",
+             "null_count": 0,
+             "max_value": "producer",
+             "min_value": "\\N"
+           }
+         }
+       },
+       {
+         "file_offset": 0,
+         "meta_data": {
+           "type": "BYTE_ARRAY",
+           "encodings": [
+             "PLAIN"
+           ],
+           "path_in_schema": [
+             "principals",
+             "characters",
+             "list",
+             "element"
+           ],
+           "codec": "SNAPPY",
+           "num_values": 10,
+           "total_uncompressed_size": 0,
+           "total_compressed_size": 50,
+           "data_page_offset": 467,
+           "statistics": {
+             "max": "\\N",
+             "min": "[\"Self\"]",
+             "max_value": "\\N",
+             "min_value": "[\"Self\"]"
+           }
+         }
+       }
+     ],
+     "total_byte_size": 0,
+     "num_rows": 10,
+     "file_offset": 4
+   }
+ ],
+ "created_by": "DuckDB",
+ "metadata_length": 690
+}
diff --git a/test/files/duckdb3734.parquet b/test/files/duckdb3734.parquet
new file mode 100644
index 0000000..4a27b9f
Binary files /dev/null and b/test/files/duckdb3734.parquet differ