This review may contain spoilers

A grizzled man, Lee Chambers (Ian Tracey), sits looking out the window at a truck stop. The waitress, Marlene (Paula Lindberg), notes that he has been there a couple of days in row. He stands up to pay, exposing the large knife he carries as a prostitute, Sally (Meghan Ory), leaves with a trucker. Lee follows them into the maze of parked trucks with his weapon drawn, but they have somehow disappeared. The waitress surprises him. His vision begins to waver due to the poison she put in his coffee. "We are venomous, you know," she says as her eyes and teeth go snake. He lunges at her with his knife, but she easily bests him.

Sam (Jared Padalecki) and Dean (Jensen Ackles) sit stunned in Bobby's cabin mourning his death. For three weeks they rattle around, Dean obsesses about the numbers Bobby wrote on Sam's hand, and Sam helps research while also cleaning and tidying. Bobby's cell rings and Sam answers. A hunter's young daughter is calling for Bobby; she hangs up on Sam. Sam wants to track down and help the girl, but Dean wants to find out why Frank (Kevin R. McNally) has not responded about the numbers. As the boys decide to split up, the contents of Dean's beer bottle disappear with a wind sound effect. They notice it, but don't recognize it as signs of Ghost Bobby (or better yet, Angel Bobby ... maybe vessel-less Castiel?).

Sam finds Chrissy (Madison McLaughlin) via Bobby's address book. Sam will help find her missing father, Lee, in Bobby's stead. Chrissy seems to think that her dad is a salesman. He usually calls every night, but it's been five days. He finds Lee's tracking board in the back of his closet. Sam takes a picture of Chrissy and Lee, leaving her with a backup phone number to call and a promise to check in himself. She is skeptical.

Sam soon discovers that three truckers are missing, in the same area that Lee disappeared, and is shown a corpse that looks like it was killed by vampires. Sam calls to report to Dean's voice mail that the monster is probably a vetala, which can be killed with a silver knife to the heart. But don't forget to twist the knife. They like to take their victims home and slowly eat them; so there's a chance that Chrissy's dad can be rescued. He shows Lee's picture to Marlene, who directs him to Sally. She plays Sam until Marlene appears and overpowers Sam. Snaked out, Sally bites Sam on the neck, fade to black.

Dean finds Frank's place emptied out but for a suspicious and well armed Frank. Dean and Frank prove that they are not leviathan with blood. When Frank began research on Dick Roman and the numbers, he was digitally attacked, so he fled. The numbers (45489), Frank tells him, mean nothing; so he expanded his search to six numbers, and he finds the coordinates to farmland in Wisconsin, recently purchased by a Roman Enterprises subsidiary. He suggests that if they are stupid they should go set up surveillance on the place.

Once there, Dick's surveillance equipment blankets the area already; so Frank taps into it instead of installing his own. In his equipment filled RV, Frank notes Dean's drained and weary appearance before Dean falls asleep in his chair for a day and a half. Frank has been watching workers surveying the area preparing to build ... something. He's patiently waiting for more information.

Dean listens to Sam's message about vetala, interrupted by Chrissy dutifully calling since Sam failed to report in. Sam wakes in a room with two bodies and Lee, weak but alive. Dean visits Chrissy, but she destroyed Lee's information, forcing Dean to take her with. On Chrissy's hunch, Dean tracks Marlene to their lair. He handcuffs Chrissy to his car's steering wheel, hoping to keep her safe. Chrissy thinks that they are too late to rescue Lee and Sam, and that they must both be dead by now. She wants vengeance.

Dean is battling vetala when resourceful Chrissy enters the fray and is immediately taken hostage. Chrissy plays helpless for a while, but it turns out she has a silver knife. She kills Sally and Sam dispatches Marlene.

The boys visit Lee in the hospital and convince him to quit for Chrissy's sake. Chrissy catches Dean as he is leaving; she doesn't mind having been an active hunter for only one event and is really warming to the idea of university. Signposting the handover from Bobby to Frank, Dean takes Frank's advice to ignore his angst and just smile.

Points Of Interest

1. The episode title references a 1987 movie starring Elisabeth Shue.

2. Mysteriously disappearing beer, it means something.

3. Dean paid Frank $15,000 to investigate Dick Roman and Bobby's numbers. The boys need to save Frank's life in some dramatic way so he'll stop charging them for services.

4. Frank has a very weak grasp on the passage of time.

5. The coordinates Frank found (45"4' 89"3') are not an exact match for 454895 seen in "Death's Door." Typo or important plot point?

6. Frank was 26 when he found his wife and two kids gutted on the floor of his house. He has been pretending to be ok ever since.

7. Lee reports that you die after 3-4 feedings from a vetala.

8. Vetala usually hunt in pairs, but John Winchester recorded an encounter with a lone vetala in his journal, and that version has spread to other hunters. Hunters need a better information distribution network.

9. In Hindu folklore, a vetala is a evil ghost with knowledge of past and future that possesses corpses. It is repelled by mantras and laid to rest with proper funerary rites. Sounds like a perfect "Supernatural" monster. When I saw the snake eyes and Marlene mentioned venom, I thought she was probably a lamia.

What Worked

Tough and clever Chrissy, MVP on her first hunt, but dreams of college, was a great character.

Frank is a fun guy if teetering a little close to the brink of too quirky.

"You think it's easy to see this deep into what's real and also be bipolar with delusional ideation? There is no pill for my situation, sweetiepop."

"It's a field, not the Death Star."

What Didn't Work

Marlene was disposing of vehicles away from the truck stop and the lair so that they didn't draw suspicion. Dean and Chrissy should not have followed her in the big semi back to her lair.

Chrissy was wearing a hair clip and a pony tail. No bobby pins. You can't pick a lock with a hair clip (or elastic) that would still be wearable afterward.

Dean's face in ultra close up while he contorts his face into a forced smile was a bit strange and creepy. But maybe that's what they were going for.

Giving Credit Where Credit Is Due

"Supernatural" stars Jared Padalecki, Jensen Ackles, Kevin R. McNally, Madison McLaughlin, Ian Tracey, Paula Lindberg, Meghan Ory, Lee Vincent. "Adventures in Babysitting" was written by Adam Glas and was directed by Jeannot Szwarc.

"Supernatural" airs Fridays at 9 p.m. ET on The CW