diff --git a/src/java/org/apache/poi/sl/usermodel/TableShape.java b/src/java/org/apache/poi/sl/usermodel/TableShape.java
index 5070cf405..13c5d0dc5 100644
--- a/src/java/org/apache/poi/sl/usermodel/TableShape.java
+++ b/src/java/org/apache/poi/sl/usermodel/TableShape.java
@@ -21,10 +21,29 @@ public interface TableShape<
     S extends Shape<S,P>,
     P extends TextParagraph<S,P,?>
 > extends Shape<S,P>, PlaceableShape<S,P> {
+    /**
+     * Return the maximum number of columns.
+     * If the table contains merged cells, the number of columns might be less than the maximum.
+     *
+     * @return the maximum number of column
+     */
     int getNumberOfColumns();
     
+    /**
+     * Return the number of rows
+     *
+     * @return the row count
+     */
     int getNumberOfRows();
     
+    /**
+     * Gets a cell
+     *
+     * @param row the row index (0-based)
+     * @param col the column index (0-based)
+     * @return the cell or null if the cell doesn't exists, e.g. when accessing
+     *         a merged cell or if the index is out of bounds
+     */
     TableCell<S,P> getCell(int row, int col);
     
     /**
diff --git a/src/ooxml/java/org/apache/poi/xslf/usermodel/XSLFTable.java b/src/ooxml/java/org/apache/poi/xslf/usermodel/XSLFTable.java
index d0d474944..21472d709 100644
--- a/src/ooxml/java/org/apache/poi/xslf/usermodel/XSLFTable.java
+++ b/src/ooxml/java/org/apache/poi/xslf/usermodel/XSLFTable.java
@@ -55,7 +55,6 @@ public class XSLFTable extends XSLFGraphicFrame implements Iterable<XSLFTableRow
     private CTTable _table;
     private List<XSLFTableRow> _rows;
 
-    @SuppressWarnings("deprecation")
     /*package*/ XSLFTable(CTGraphicalObjectFrame shape, XSLFSheet sheet){
         super(shape, sheet);
 
@@ -83,7 +82,21 @@ public class XSLFTable extends XSLFGraphicFrame implements Iterable<XSLFTableRow
 
     @Override
     public XSLFTableCell getCell(int row, int col) {
-        return getRows().get(row).getCells().get(col);
+        List<XSLFTableRow> rows = getRows();
+        if (row < 0 || rows.size() <= row) {
+            return null;
+        }
+        XSLFTableRow r = rows.get(row);
+        if (r == null) {
+            // empty row
+            return null;
+        }
+        List<XSLFTableCell> cells = r.getCells();
+        if (col < 0 || cells.size() <= col) {
+            return null;
+        }
+        // cell can be potentially empty ...
+        return cells.get(col);
     }
     
     @Internal
diff --git a/src/scratchpad/src/org/apache/poi/hslf/usermodel/HSLFShapeFactory.java b/src/scratchpad/src/org/apache/poi/hslf/usermodel/HSLFShapeFactory.java
index 4fe197782..737d2927a 100644
--- a/src/scratchpad/src/org/apache/poi/hslf/usermodel/HSLFShapeFactory.java
+++ b/src/scratchpad/src/org/apache/poi/hslf/usermodel/HSLFShapeFactory.java
@@ -58,7 +58,7 @@ public final class HSLFShapeFactory {
             for (EscherProperty ep : props) {
                 if (ep.getPropertyNumber() == EscherProperties.GROUPSHAPE__TABLEPROPERTIES
                     && ep instanceof EscherSimpleProperty
-                    && ((EscherSimpleProperty)ep).getPropertyValue() == 1) {
+                    && (((EscherSimpleProperty)ep).getPropertyValue() & 1) == 1) {
                     isTable = true;
                     break;
                 }
diff --git a/src/scratchpad/src/org/apache/poi/hslf/usermodel/HSLFTable.java b/src/scratchpad/src/org/apache/poi/hslf/usermodel/HSLFTable.java
index 814ffe745..b82bed34a 100644
--- a/src/scratchpad/src/org/apache/poi/hslf/usermodel/HSLFTable.java
+++ b/src/scratchpad/src/org/apache/poi/hslf/usermodel/HSLFTable.java
@@ -52,6 +52,7 @@ implements HSLFShapeContainer, TableShape<HSLFShape,HSLFTextParagraph> {
 
 
     protected HSLFTableCell[][] cells;
+    private int columnCount = -1;
 
     /**
      * Create a new Table of the given number of rows and columns
@@ -114,20 +115,31 @@ implements HSLFShapeContainer, TableShape<HSLFShape,HSLFTextParagraph> {
         super(escherRecord, parent);
     }
 
-    /**
-     * Gets a cell
-     *
-     * @param row the row index (0-based)
-     * @param col the column index (0-based)
-     * @return the cell
-     */
+    @Override
     public HSLFTableCell getCell(int row, int col) {
-        return cells[row][col];
+        if (row < 0 || cells.length <= row) {
+            return null;
+        }
+        HSLFTableCell[] r = cells[row];
+        if (r == null || col < 0 || r.length <= col) {
+            // empty row
+            return null;
+        }
+        // cell can be potentially empty ...
+        return r[col];
     }
 
     @Override
     public int getNumberOfColumns() {
-        return cells[0].length;
+        if (columnCount == -1) {
+            // check all rows in case of merged rows
+            for (HSLFTableCell[] hc : cells) {
+                if (hc != null) {
+                    columnCount = Math.max(columnCount, hc.length);
+                }
+            }
+        }
+        return columnCount;
     }
 
     @Override
diff --git a/src/scratchpad/testcases/org/apache/poi/hslf/usermodel/TestBugs.java b/src/scratchpad/testcases/org/apache/poi/hslf/usermodel/TestBugs.java
index 6e11a41b5..68684bf8d 100644
--- a/src/scratchpad/testcases/org/apache/poi/hslf/usermodel/TestBugs.java
+++ b/src/scratchpad/testcases/org/apache/poi/hslf/usermodel/TestBugs.java
@@ -768,6 +768,15 @@ public final class TestBugs {
             ex.close();
         }
     }
+
+    @Test
+    public void bug58733() throws IOException {
+        File sample = HSLFTestDataSamples.getSampleFile("bug58733_671884.ppt");
+        PowerPointExtractor ex = new PowerPointExtractor(sample.getAbsolutePath());
+        assertNotNull(ex.getText());
+        ex.close();
+    }
+
     
     private static HSLFSlideShow open(String fileName) throws IOException {
         File sample = HSLFTestDataSamples.getSampleFile(fileName);
diff --git a/test-data/slideshow/bug58733_671884.ppt b/test-data/slideshow/bug58733_671884.ppt
new file mode 100644
index 000000000..08c46e055
Binary files /dev/null and b/test-data/slideshow/bug58733_671884.ppt differ