Warning: The following contains spoilers for The Rookie Season 4, Episode 15, "Hit List," which aired Sunday, March 6th on ABC.

Last week’s episode of The Rookie hilariously introduced Skip Tracer Randy. Becoming an awful bounty hunter for a day, Randy worked with Nolan and Harper to catch a Hollywood madam. The latest installment “Hit List,” however, took a much more serious tone. One of the LAPD’s finest was injured and it looks like he could be gearing up to leave the series. Here’s what happened and why Sergeant Wade Grey could be on his way out.

Officer Nolan, to his chagrin, spent the early part of his shift working the front desk with the notoriously lazy Officer Smitty. Because Smitty wouldn’t do much, Nolan was handling everyone in line. But when he thought he was done, there was one man still sitting in a chair -- and he was dead. The duo saw from security footage that someone else had injected the man with a substance that killed him inside of the police station.

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The Rookie Sergeant Grey 2

Bradford and Chen witnessed a drive-by shooting soon afterward, and the timing wasn’t a coincidence. Both victims were witnesses in a big-time case against a mob boss named Matteo Rubio. Someone had leaked the witness list and Rubio’s people had employed a pair of hired guns. The next hit was much more personal, as a highly skilled female assassin (like Star Wars’ Fennec Shand) shot Sergeant Grey in a parking garage. Grey survived the attack and ended up killing his assailant. By identifying the dead hitwoman, the LAPD was able to catch the lawyer that leaked the witness list. From there, they arrested the other hitman -- therefore saving Lucy’s almost-boyfriend ADA Chris Sanford and the prosecutor who was handling the case against Rubio.

While the day ended up being a success, Sergeant Grey was noticeably shaken after his near-death experience. Besides being in pain and feeling old, he noted that the hitwoman was the first person that he had ever killed. That was taking a toll on him, as was his wife constantly worrying about his safety. From his comments, it seemed like he was considering retirement right then and there, but at the end of the episode there was more than a hint that the character might be on his way out.

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The Rookie Sergeant Grey in the hospital

As Grey was sitting in his hospital bed, Bradford jokingly said that getting shot would force Grey to take a trial run at retirement. That line could be nothing, but Bradford’s comment felt like the first domino that would lead to Grey’s exit at the end of Season 4. It was already odd when Bradford was promoted to Sergeant this season when the The Rookie already had one -- unless the writers were setting him up to take Grey's slot on a permanent basis.

Should that come to pass, it wouldn’t be the first time that The Rookie has lost an original cast member. Midway through Season 1, Captain Zoe Andersen was killed. Then at the beginning of Season 2, the series wrote off Officer Talia Bishop. Most recently, Officer Jackson West died during Season 4. Hopefully Grey isn’t about to leave, but even if he does, The Rookie has proven that it can replace key characters and maintain its success.

To see if Sergeant Grey is written off, tune into The Rookie. New episodes air on Sundays at 10:00 p.m. ET/PT on ABC.

KEEP READING: The Rookie: Chen and Bradford Stop a Frankenstein – but Chenford Takes a Hit