diff --git a/lib/calcms/series.pm b/lib/calcms/series.pm
index 999dba2..eb0facc 100644
--- a/lib/calcms/series.pm
+++ b/lib/calcms/series.pm
@@ -1158,6 +1158,57 @@ sub is_event_assigned_to_user ($$) {
     return 1;
 }
 
+sub get_rebuilt_episodes ($$) {
+    my $config  = shift;
+    my $options = shift;
+
+    return "missing project_id" unless defined $options->{project_id};
+    return "missing studio_id"  unless defined $options->{studio_id};
+    return "missing series_id"  unless defined $options->{series_id};
+
+    # ignore project and studio as series can be used in multiple studios
+    my $events = series::get_events(
+        $config,
+        {
+            #project_id => $options->{project_id},
+            #studio_id  => $options->{studio_id},
+            series_id  => $options->{series_id},
+            draft      => 0
+        }
+    );
+    @$events = sort { $a->{start} cmp $b->{start} } @$events;
+
+    my $events_by_episode = {};
+    for my $event (@$events) {
+        next unless $event->{episode};
+        push @{ $events_by_episode->{$event->{episode}} }, $event;
+    }
+
+    my $done={};
+    my $episode = $events->[0]->{episode} // 0;
+    $episode-=1;
+
+    for my $i (0..$#$events){
+        my $event = $events->[$i];
+        next if $done->{$event->{id}};
+        $episode++;
+        # increase episode for not set values
+        if ( ($event->{episode}//'') eq ''){
+            $event->{old_episode} = $event->{episode};
+            $event->{episode} = $episode;
+            next;
+        }
+        # set new value to all episodes with same value
+        for my $event2 (@{$events_by_episode->{$event->{episode}}}){
+            $event2->{old_episode} = $event2->{episode};
+            $event2->{episode} = $episode;
+            $done->{$event2->{id}}=1;
+        };
+    }
+    #print STDERR Dumper($events);
+    return $events;
+}
+
 # to find multiple recurrences this does not include the recurrence_count
 # use events::get_key to add the recurrence
 sub get_event_key ($) {
@@ -1191,8 +1242,8 @@ sub update_recurring_events ($$) {
     my $events = series::get_events(
         $config,
         {
-            project_id => $options->{project_id},
-            studio_id  => $options->{studio_id},
+            #project_id => $options->{project_id},
+            #studio_id  => $options->{studio_id},
             series_id  => $options->{series_id},
             draft      => 0
         }
@@ -1209,7 +1260,7 @@ sub update_recurring_events ($$) {
     }
 
     # handle all events with the same key
-    for my $key ( keys %$events_by_key ) {
+    for my $key ( sort keys %$events_by_key ) {
         my $events = $events_by_key->{$key};
         next unless scalar @$events > 0;
 
@@ -1219,8 +1270,6 @@ sub update_recurring_events ($$) {
             my $event = $events->[0];
             next if $event->{recurrence} == 0;
             next if $event->{recurrence_count} == 0;
-            print STDERR
-"remove recurrence\t'$event->{event_id}'\t'$event->{start}'\t'$event->{rerun}'\t'$event->{recurrence}'\t'$event->{key}'\n";
             $event->{recurrence}       = 0;
             $event->{recurrence_count} = 0;
             $event->{rerun}            = 0;
@@ -1232,14 +1281,10 @@ sub update_recurring_events ($$) {
             # first event is the original
             my $event      = $events->[0];
             my $originalId = $event->{event_id};
-            print STDERR
-"0\t'$event->{recurrence_count}'\t'$event->{event_id}'\t'$event->{start}'\t'$event->{rerun}'\t'$event->{recurrence}'\t'$event->{key}'\n";
 
             # succeeding events are reruns
             for ( my $c = 1 ; $c < scalar(@$events) ; $c++ ) {
                 my $event = $events->[$c];
-                print STDERR
-"$c\t'$event->{recurrence_count}'\t'$event->{event_id}'\t'$event->{start}'\t'$event->{rerun}'\t'$event->{recurrence}'\t'$event->{key}'\n";
 
                 my $update = 0;
                 $update = 1 if $event->{recurrence} ne $originalId;
diff --git a/lib/calcms/series_events.pm b/lib/calcms/series_events.pm
index e912d60..4a6ccd7 100644
--- a/lib/calcms/series_events.pm
+++ b/lib/calcms/series_events.pm
@@ -41,8 +41,6 @@ sub save_content($$) {
     my $config = shift;
     my $entry  = shift;
 
-    my $dbh = db::connect($config);
-
     return undef unless ( defined $entry->{id} );
 
     for my $attr ( keys %$entry ) {
@@ -100,15 +98,35 @@ sub save_content($$) {
 		where  id=?
 	};
 
-    #print STDERR "update:".$query.Dumper(\@bind_values);
+    my $dbh = db::connect($config);
     my $result = db::put( $dbh, $query, \@bind_values );
     unless ( defined $result ) {
         print STDERR "error on updating event\n";
         return undef;
     }
 
-    #print STDERR "result=$result\n";
-    #print STDERR "entr after update".Dumper($entry);
+    return $entry;
+}
+
+sub set_episode{
+    my $config = shift;
+    my $entry  = shift;
+
+    return undef unless ( defined $entry->{id} );
+    return undef unless ( defined $entry->{episode} );
+
+    my $query = qq{
+		update calcms_events 
+		set    episode=?
+		where  id=?
+	};
+    my $bind_values= [ $entry->{episode}, $entry->{id} ];
+    my $dbh = db::connect($config);
+    my $result = db::put( $dbh, $query, $bind_values );
+    unless ( defined $result ) {
+        print STDERR "error on setting episode in event\n";
+        return undef;
+    }
     return $entry;
 }
 
diff --git a/website/agenda/planung/calendar.cgi b/website/agenda/planung/calendar.cgi
index 7b1ca8b..e1ad26b 100755
--- a/website/agenda/planung/calendar.cgi
+++ b/website/agenda/planung/calendar.cgi
@@ -109,6 +109,7 @@ if (
             <!--<link href="css/theme.default.css" rel="stylesheet">-->
             <script src="js/jquery.tablesorter.min.js"></script>
             <script src="js/jquery.tablesorter.widgets.min.js"></script>
+            <style>#content{ top:5rem; position:relative; }</style>
         };
     }
 }
diff --git a/website/agenda/planung/pot/de/series.po b/website/agenda/planung/pot/de/series.po
index a567384..e1db460 100644
--- a/website/agenda/planung/pot/de/series.po
+++ b/website/agenda/planung/pot/de/series.po
@@ -22,6 +22,9 @@ msgstr "Alte Sendereihen"
 msgid "button_show_changes"
 msgstr "Änderungen"
 
+msgid "button_rebuild_episodes"
+msgstr "Episoden neuzählen"
+
 msgid "label_name"
 msgstr "Name"
 
diff --git a/website/agenda/planung/pot/en/series.po b/website/agenda/planung/pot/en/series.po
index 942d4f1..26c1642 100644
--- a/website/agenda/planung/pot/en/series.po
+++ b/website/agenda/planung/pot/en/series.po
@@ -22,6 +22,9 @@ msgstr "old series"
 msgid "button_show_changes"
 msgstr "changes"
 
+msgid "button_rebuild_episodes"
+msgstr "recount episodes"
+
 msgid "label_name"
 msgstr "name"
 
diff --git a/website/agenda/planung/series.cgi b/website/agenda/planung/series.cgi
index 75153f7..8e472bd 100755
--- a/website/agenda/planung/series.cgi
+++ b/website/agenda/planung/series.cgi
@@ -93,14 +93,20 @@ if ( defined $params->{action} ) {
         my $result = reassign_event( $config, $request );
         return if defined $result;
     }
+    if ($params->{action} eq 'rebuild_episodes'){
+        rebuild_episodes($config, $request);
+        return;
+    };
+    if ($params->{action} eq 'set_rebuilt_episodes'){
+        set_rebuilt_episodes($config, $request);
+        return;
+    };
 
     #    save_scan    ($config, $request)    if ($params->{action} eq 'save_scan');
 }
 
 $config->{access}->{write} = 0;
 
-#print STDERR "show_series\n";
-
 if ( defined $params->{series_id} ) {
     print q{<script src="js/edit-series.js" type="text/javascript"></script>} unless params::isJson();
     show_series( $config, $request );
@@ -111,6 +117,7 @@ if ( defined $params->{series_id} ) {
     } unless params::isJson();
     list_series( $config, $request );
 }
+
 return;
 
 #insert or update a schedule and update all schedule dates
@@ -351,7 +358,6 @@ sub save_series {
         return;
     }
 
-    #print STDERR Dumper($entry);
     my $series_ids = series::get(
         $config,
         {
@@ -1224,6 +1230,160 @@ sub show_series {
     template::process( $config, 'print', $params->{template}, $params );
 }
 
+sub set_rebuilt_episodes{
+    my $config  = shift;
+    my $request = shift;
+
+    $config->{access}->{write} = 0;
+
+    my $params      = $request->{params}->{checked};
+    my $permissions = $request->{permissions};
+    unless ( $permissions->{read_series} == 1 ) {
+        uac::permissions_denied('read_series');
+        return;
+    }
+
+    for my $param ( 'project_id', 'studio_id', 'series_id' ) {
+        unless ( defined $params->{$param} ) {
+            uac::print_error("missing $param");
+            return;
+        }
+    }
+
+    unless ( project::is_series_assigned( $config, $params ) == 1 ) {
+        uac::print_error('series is not assigned to project!');
+        return undef;
+    }
+
+    #this will be updated later (especially allow_update_events)
+    for my $permission ( keys %{ $request->{permissions} } ) {
+        $params->{'allow'}->{$permission} = $request->{permissions}->{$permission};
+    }
+
+    my $project_id = $params->{project_id};
+    my $studio_id  = $params->{studio_id};
+    my $series_id  = $params->{series_id};
+    my $events = series::get_rebuilt_episodes( $config, {
+        project_id => $project_id,
+        studio_id  => $studio_id,
+        series_id  => $series_id
+    });
+
+    my $updates = 0;
+    for my $event (@$events){
+        next if $event->{project_id} ne $project_id;
+        next if $event->{studio_id} ne $studio_id;
+        next if $event->{old_episode} eq $event->{episode};
+        series_events::set_episode( $config, {
+            id       => $event->{id}, 
+            episode  => $event->{episode}
+        });
+        $updates++;
+    }
+    print "$updates changes done.\n";
+}
+
+sub rebuild_episodes{
+    my $config  = shift;
+    my $request = shift;
+
+    $config->{access}->{write} = 0;
+
+    my $params      = $request->{params}->{checked};
+    my $permissions = $request->{permissions};
+    unless ( $permissions->{read_series} == 1 ) {
+        uac::permissions_denied('read_series');
+        return;
+    }
+
+    for my $param ( 'project_id', 'studio_id', 'series_id' ) {
+        unless ( defined $params->{$param} ) {
+            uac::print_error("missing $param");
+            return;
+        }
+    }
+
+    unless ( project::is_series_assigned( $config, $params ) == 1 ) {
+        uac::print_error('series is not assigned to project!');
+        return undef;
+    }
+
+    #this will be updated later (especially allow_update_events)
+    for my $permission ( keys %{ $request->{permissions} } ) {
+        $params->{'allow'}->{$permission} = $request->{permissions}->{$permission};
+    }
+
+    my $project_id = $params->{project_id};
+    my $studio_id  = $params->{studio_id};
+    my $series_id  = $params->{series_id};
+    my $events = series::get_rebuilt_episodes( $config, {
+        project_id => $project_id,
+        studio_id  => $studio_id,
+        series_id  => $series_id
+    });
+
+    my $events_by_id={};
+    for my $event (@$events){
+        $events_by_id->{$event->{id}} = $event;
+    }
+
+    print "<style>
+        tr        {cursor:pointer}
+        td        {border:1px solid gray}
+        tr.error  {background:#f99}
+        tr.warn   {background:#ff9}
+        tr.ok     {background:#9f9}
+        </style>
+    ";
+
+    my $prev=undef;
+    my $max_episode=0;
+    my $changes=0;
+    my $errors=0;
+    for my $event (@$events){
+        $max_episode = $event->{episode} if $event->{episode} > $max_episode;
+        my $e1 = $event->{old_episode} //'';
+        my $e2 = $event->{episode}     //'';
+        my $o1 = $prev->{old_episode}  //'';
+        my $o2 = $prev->{episode}      //'';
+        if ($e1 eq $e2){
+            $event->{class} = 'ok';
+        }else{
+            $changes++;
+            $event->{class} = 'warn';
+        }
+        if ($e1 and $e2 and $o1 and $o2 and ( ($e2-$o2) != ($e1-$o1) ) ){
+            $event->{class} = "error" if $e1 ne $e2;
+            $prev->{class} = "error" if defined $prev and $o1 ne $o2;
+            $errors++;
+        }
+        if ($event->{episode} < $max_episode and !$event->{recurrence}){
+            $event->{class} = "error";
+            $errors++;
+        }
+        $event->{recurrence_start} = $events_by_id->{$event->{recurrence}}->{start};
+        $event->{recurrence} = '-' unless $event->{recurrence};
+        $prev = $event;
+    }
+    print "$errors errors, $changes changes\n";
+    if ( ($changes>0) and ($errors==0) ){
+        my $url = "series.cgi?action=set_rebuilt_episodes&project_id=$project_id&studio_id=$studio_id&series_id=$series_id";
+        print qq{<a class="button" href="$url"><button>apply changes</button></a>};
+    }
+    my @cols=qw(id start series_name title episode old_episode recurrence recurrence_start project_name studio_name);
+    print "<table>\n";
+    print "<tr>" . join ("", map { "<th>".($_ // '-')."</th>" } @cols) . "</tr>\n" ;
+        
+    for my $event (@$events){
+        print qq{<tr class="$event->{class}" onclick="window.location.href=\$(this).attr('href');"}
+            . qq{ href="event.cgi?action=edit&project_id=$event->{project_id}&studio_id=$event->{studio_id}&series_id=$series_id&event_id=$event->{id}"\n}
+            . qq{>}
+            . join ("", map { "<td>".($event->{$_}//'-')."</td>" } @cols) 
+            . "</tr>\n";
+    }
+    print "</table>\n";
+}
+
 sub check_params {
     my $config = shift;
     my $params = shift;
@@ -1239,16 +1399,14 @@ sub check_params {
     #actions and roles
     $checked->{action} = '';
     if ( defined $params->{action} ) {
-        if ( $params->{action} =~
-/^(add_user|remove_user|create|delete|save|details|show|save_schedule|delete_schedule|save_scan|scan_events|assign_event|unassign_event|reassign_event)$/
-          )
-        {
-            $checked->{action} = $params->{action};
-        }
+        $checked->{action} = $params->{action} if $params->{action} =~
+/^(add_user|remove_user|create|delete|save|details|show|save_schedule|delete_schedule|save_scan|scan_events|assign_event|unassign_event|reassign_event|rebuild_episodes|set_rebuilt_episodes)$/
+        ;
     }
 
     #numeric values
     $checked->{exclude} = 0;
+    $checked->{action} = $params->{action};
     for my $param (
         'id',            'project_id',                'studio_id', 'default_studio_id',
         'user_id',       'new_series_id',             'series_id', 'schedule_id',
diff --git a/website/agenda/planung/templates/edit-series.html b/website/agenda/planung/templates/edit-series.html
index 73b2064..9dabc9d 100644
--- a/website/agenda/planung/templates/edit-series.html
+++ b/website/agenda/planung/templates/edit-series.html
@@ -56,6 +56,16 @@
 	            <button type="submit" name="action"     value="show_new_event"><TMPL_VAR .loc.button_create_event></button>
 	        </form>
 	    </TMPL_IF>
+
+	    <TMPL_IF .allow.update_event>
+	        <form action="series.cgi">
+	            <input  type="hidden" name="project_id" value="<TMPL_VAR .project_id>">
+	            <input  type="hidden" name="studio_id"  value="<TMPL_VAR .studio_id>">
+	            <input  type="hidden" name="series_id"  value="<TMPL_VAR .series_id>">
+	            <button type="submit" name="action"     value="rebuild_episodes"><TMPL_VAR .loc.button_rebuild_episodes></button>
+	        </form>
+	    </TMPL_IF>
+
     </div>
 
 	<div class="panel-header">