Rumors swirled that the return of serial killer Red John on the Nov. 19 episode of The Mentalist would claim a regular cast member. And sure enough, CBI agent Sam Bosco took a bullet. He lingered in the hospital for a spell, but after a few heart-to-hearts, his own ticker stopped for good. Here, actor Terry Kinney opens up exclusively to TV Guide Magazine about his too-short stint on CBS’s top ten hit.

My sympathies on your untimely demise. And to add salt to the wound, your killer turned out to be your devious secretary who was having an affair with Red John. Not Red John himself!
Well, Red John has highly influential minions. And it certainly seems that he’s a serial killer with money.

This was not a total surprise because you sort of let it be known that the role was temporary.
Yes. I knew going in that my demise was imminent. There was a sense of freedom for me because from the outset there was a finite nature. I just had to keep quiet about it.

What was the highlight of your time on the show?
Pretending that I don’t like Jane is fun because Simon and I actually hit it off very quickly. Both of us have an attention to detail and like to question every single moment. And we always like to be playful. When he realized that he couldn’t throw me off, he decided he was going to have fun working with me.

Shortly before he died, Bosco told Teresa (Robin Tunney) that he loved her. What was your interpretation of that admission?
I think all this time anyone watching might have thought they were hiding some kind of dirty secret or affair. And really, I think the beauty in the end is that nothing happened between them physically, but there was always an unspoken deep affection and love, which he never had the nerve to tell her.

Was it important to you that this be addressed?
It was. And there were questions about it because sometimes what people don’t say has more gravitas than what is spoken. We talked about it a lot. But in the end, we felt that admission had been earned.

Do you have any lingering questions about Bosco?
The thing that will probably come out later about this character is what Lisbon might have done on his behalf in regards to police work that perhaps wasn’t completely above board. When our characters were first working together, something happened that we share as a secret. I have a feeling he may have done something to a bad guy that ensured he wouldn’t be able to continue.

How were you celebrated on your final day?
On my last day I was in the hospital bed and (show creator) Bruno Heller came to the set late at night. Everyone gathered and it was very moving. I really got that they wanted me to stay, but the integrity of that arc had to be honored.

Why knock off this integral character?
They wanted a temporary spice between my character and Simon Baker’s (Patrick Jane), but ultimately the gravity of the search for Red John had to be realized.

Did you receive a cake with a big red smiley face on it?
(Laughs) You know, when I came to do my last episode, I saw the wall with the smiley face, and I went ‘Ah f—.’ Actually, they gave me a bottle of champagne that I won’t touch. I’m just going to leave it in my refrigerator to remember them by.

The episode also marked Gregory Itzin’s farewell as Lisbon’s boss, Virgil Minelli. Did you get to know him well?
I did. What a lovely guy. He was incredibly sad. When he left, he brought me a little straw fedora because he noticed I always wear hats. But he just dropped it in my trailer. He didn’t stop to say ‘goodbye’. He took off. Everyone said that when he was done he slipped out the back door because I think he was sad about it. I did the opposite. I went around hugging everybody forever until they were probably like, ‘Get out – you’re dead!’

So Greg wasn’t expecting this?
I think he was as surprised as anybody. I don’t know that his character was meant to be finite. We did joke with each other about our leaving – who goes first? And if either of us was going to get a monologue.

Last question. If you had to guess who Red John is, who would you guess?
I always felt it should be a very handsome, and well-to-do person. And played by someone well known to us.

So maybe you, coming back as Bosco’s long-lost twin?
A guy with a little more hair and glasses… Oh no. We talked about that, but I just got a laugh.

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