diff --git a/Tusker/Screens/Large Image/Transitions/LargeImageInteractionController.swift b/Tusker/Screens/Large Image/Transitions/LargeImageInteractionController.swift
index 4f8618b0..562846a8 100644
--- a/Tusker/Screens/Large Image/Transitions/LargeImageInteractionController.swift	
+++ b/Tusker/Screens/Large Image/Transitions/LargeImageInteractionController.swift	
@@ -25,7 +25,14 @@ class LargeImageInteractionController: UIPercentDrivenInteractiveTransition {
     }
     
     @objc func handleGesture(_ recognizer: UIPanGestureRecognizer) {
-        let translation = recognizer.translation(in: recognizer.view!.superview!)
+        guard let recognizerSuperview = recognizer.view?.superview else {
+            // Assume the gesture has ended b/c we don't have a view/superview anymore.
+            inProgress = false
+            direction = nil
+            cancel()
+            return
+        }
+        let translation = recognizer.translation(in: recognizerSuperview)
         var progress = translation.y / 200
         if let direction = direction {
             progress *= direction
@@ -63,7 +70,7 @@ class LargeImageInteractionController: UIPercentDrivenInteractiveTransition {
     
     override func cancel() {
         super.cancel()
-        viewController.isInteractivelyAnimatingDismissal = false
+        viewController?.isInteractivelyAnimatingDismissal = false
     }
     
 }