The Mentalist Season 5 returns Sunday with a new episode (19) called, "Red Letter Day." The series is drawing closer to its season finale. From the spoilers we've read, Patrick Jane's hunt for Red John will see a major change. How? Avid viewers can only speculate until then.

The Mentalist has earned a Season 6 deal with CBS. This means a major cliffhanger could be seen in a month's time. It is expected that Homeland mystery man Bob Kirkland will have a big role in this season's finale. In this week's episode, he tries to find out how much Jane knows about Red John.

Jane has lost another Red John accomplice, this time in the hands of Kirkland. He has no proof, but Jane threw a meaningful look at Kirkland upon learning of Jason Lennon's death. Many Mentalist followers doubt Kirkland is RJ himself, but he could be a staunch ally of the evil villain. Are we in for a Patrick Jane vs Bob Kirkland mind showdown in the Season 5 finale?

Red John has always been at least two steps ahead of Patrick Jane in the previous season finales. In last year's chapter ending, Jane got hold of Lorelei Martins. This year, we are left with only Kirkland (so far). How could Jane get more intel about the monstrous murderer who killed his wife and daughter?

The Mentalist creator Bruno Heller has previously teased fans that he may have already cast Red John. This is why Jane's little book of suspects is crucial for the fans to answer: "Who is Red John?"

Tom Szentgyorgyi, a Mentalist writer has a more generous teaser about the upcoming Season 5 finale. He recently told TV Guide:

"This season has been about Jane digging into the notion that it's not that Red John could be anyone; it's that Red John is one of a very specific set of people that Jane is uniquely qualified to investigate." This could only mean that Jane should not look too far for clues about RJ. "The finale is going to pay that off in a way that will completely change the hunt for Red John. We are going to know some very specific things about who he might be."

We also learned that Mentalist Season 5 viewers will soon be introduced to a "psychic" named Sean Barlow. Tune in until the finale airs on May 5.

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