diff --git a/release/play_abstreet.bat b/release/play_abstreet.bat
index 7dfb6a6a53..894494fe58 100755
--- a/release/play_abstreet.bat
+++ b/release/play_abstreet.bat
@@ -1,3 +1,3 @@
 cd game
 set RUST_BACKTRACE=1
-game.exe 1> ..\\output.txt 2>&1
+game.exe --rng_seed=42 1> ..\\output.txt 2>&1
diff --git a/release/play_abstreet.sh b/release/play_abstreet.sh
index 92409908dc..eab7694571 100755
--- a/release/play_abstreet.sh
+++ b/release/play_abstreet.sh
@@ -1,4 +1,4 @@
 #!/bin/bash
 
 cd game
-RUST_BACKTRACE=1 ./game
+RUST_BACKTRACE=1 ./game --rng_seed=42