diff --git a/CHANGELOG.md b/CHANGELOG.md
index 08ba5acbb0..f6f3f3301f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 ## [Unreleased]
+* fix: crash when attaching to a session without the first tab (https://github.com/zellij-org/zellij/pull/1648)
 
 ## [0.31.1] - 2022-08-02
 * add: `solarized-light` theme to the example theme directory (https://github.com/zellij-org/zellij/pull/1608)
diff --git a/zellij-server/src/screen.rs b/zellij-server/src/screen.rs
index 79cbdb5706..c184e29fb1 100644
--- a/zellij-server/src/screen.rs
+++ b/zellij-server/src/screen.rs
@@ -641,11 +641,6 @@ impl Screen {
     pub fn new_tab(&mut self, layout: Layout, new_pids: Vec<RawFd>, client_id: ClientId) {
         let tab_index = self.get_new_tab_index();
         let position = self.tabs.len();
-        let client_mode_info = self
-            .mode_info
-            .get(&client_id)
-            .unwrap_or(&self.default_mode_info)
-            .clone();
         let mut tab = Tab::new(
             tab_index,
             position,
@@ -657,7 +652,7 @@ impl Screen {
             self.bus.senders.clone(),
             self.max_panes,
             self.style,
-            client_mode_info,
+            self.default_mode_info.clone(),
             self.draw_pane_frames,
             self.connected_clients.clone(),
             self.session_is_mirrored,
@@ -702,21 +697,29 @@ impl Screen {
     }
 
     pub fn add_client(&mut self, client_id: ClientId) {
-        let mut tab_index = 0;
         let mut tab_history = vec![];
-        if let Some((_first_client, first_active_tab_index)) = self.active_tab_indices.iter().next()
-        {
-            tab_index = *first_active_tab_index;
-        }
         if let Some((_first_client, first_tab_history)) = self.tab_history.iter().next() {
             tab_history = first_tab_history.clone();
         }
+
+        let tab_index = if let Some((_first_client, first_active_tab_index)) =
+            self.active_tab_indices.iter().next()
+        {
+            *first_active_tab_index
+        } else if self.tabs.contains_key(&0) {
+            0
+        } else if let Some(tab_index) = self.tabs.keys().next() {
+            tab_index.to_owned()
+        } else {
+            panic!("Can't find a valid tab to attach client to!");
+        };
+
         self.active_tab_indices.insert(client_id, tab_index);
         self.connected_clients.borrow_mut().insert(client_id);
         self.tab_history.insert(client_id, tab_history);
         self.tabs
             .get_mut(&tab_index)
-            .unwrap()
+            .unwrap_or_else(|| panic!("Failed to attach client to tab with index {tab_index}"))
             .add_client(client_id, None);
     }
     pub fn remove_client(&mut self, client_id: ClientId) {
diff --git a/zellij-server/src/unit/screen_tests.rs b/zellij-server/src/unit/screen_tests.rs
index 0cf8d45353..cbe0c1b571 100644
--- a/zellij-server/src/unit/screen_tests.rs
+++ b/zellij-server/src/unit/screen_tests.rs
@@ -544,3 +544,25 @@ fn update_screen_pixel_dimensions() {
         "empty update does not delete existing data",
     );
 }
+
+#[test]
+fn attach_after_first_tab_closed() {
+    // ensure https://github.com/zellij-org/zellij/issues/1645 is fixed
+    let size = Size {
+        cols: 121,
+        rows: 20,
+    };
+    let mut screen = create_new_screen(size);
+
+    new_tab(&mut screen, 1);
+    {
+        let active_tab = screen.get_active_tab_mut(1).unwrap();
+        active_tab.new_pane(PaneId::Terminal(2), Some(1));
+        active_tab.toggle_active_pane_fullscreen(1);
+    }
+    new_tab(&mut screen, 2);
+
+    screen.close_tab_at_index(0);
+    screen.remove_client(1);
+    screen.add_client(1);
+}