Basic Trope: A character escapes by using the bathroom, be it as an excuse or by escaping through the actual room.
Mark has a problem: he needs to get out of the manor he's been robbing, but the guards already know there's a thief running around! However, he successfully evades capture by ducking into the bathroom and escaping through the window.
Natalie has been thrown into a guarded cell. She convinces him to let her use the bathroom; once he's opened the door, she knocks him out and escapes.
Exaggerated: Natalie convinces her guard to escort her to the bathroom. Once there, she knocks him out, props his unconscious body against the door to keep it blocked, and escapes from the bathroom using only materials she finds therein.
Justified: The normal exits are blocked.
Inverted: Mark sneaks into the manor through the bathroom window.
Natalie pleads for the guard to let her go use the toilet. The guard responds by handing her a bucket.
As it turns out, Natalie actually does need to use the restroom.
After he gives her the bucket, Natalie promptly accuses him of being a sick pervert, and keeps harping on him until he finally gives in.
She decides to use her opportunity away from the guard to escape.
Parodied: Natalie convinces the guard to let her use the bathroom, only to find there's a line of people waiting there to escape.
Zig Zagged: Natalie begs the guard to let her use the toilet, but he refuses... at first. Eventually, she wears him down, and is allowed to use the restroom. He attempts to enter with her at first, but she throws him out. Just when he thinks that she's snuck out somehow, she reemerges and calmly returns to her cell. However, it turns out that the real reason she insisting on going to the bathroom was to retrieve something she could then use to break out of prison...
Averted: Natalie heads into the bathroom but finds it doesn't even have an outside wall or any air vents large enough. It is only good as a place to gather her thoughts or a brief hiding place.
Invoked: "I need to find a way to get out of here now... hey, wait a minute, in the movies they always... Hey, excuse me, I've really gotta go to the bathroom, here!"
Exploited: Dave, who is one of the guards, finds out Mark is still in the mansion and excuses himself to the bathroom, so he can meet Mark when he arrives to escape and send a message out with him.
The strongest of the guards on the mansion are stationed inside, near the bathroom.
"Now, no matter what Natalie says, don't you dare let her out of the room for any reason. Especially not to use the restroom. Clear?"
Deconstructed: The villain knows how this goes and the "escape" route in the bathroom leads deeper into the prison.
Reconstructed: However deeper in the prison also lies the control room, allowing her to release all of the prisoners.
Played For Drama: All other possible avenues of escape have been blocked off, one by one. Mark attempts to sneak into the bathroom unseen, but the door creaks just as he's closing it, alerting the guards. As they pound against the locked door, Mark hastily throws together a pitiful barricade that buys him precious seconds to jimmy open the window and squirm out.