While normally agency farewells we’ve seen are of the sentimental kind, whether it’s a heartfelt letter from a boss to a departing employee or a practical, charming video, this doozy that we received from multiple tipsters this morning is anything but. In a note sent to the entire MEC U.K. office this morning (and is now apparently blowing up on Twitter), senior account manager, interaction Kieran Allen decided to say say goodbye guns blazing, in the process picking out one select higher-up as the target of his ire.

We’re reached out to Allen himself to determine the legitimacy of this letter, but spies are telling us that it’s went out to at least four agencies already. For now, read in full below and after the jump. Of course, we’ve removed the name of Allen’s supposed foe throughout seeing as the content is none-too-flattering and leaves us wondering whether this is a legit gripe or the rants of a bitter, now-ex-employee.  It”s safe to say, though, that our scribe has burned a bridge or two. Update: Now even U.K. trade The Sun has taken notice and we’re also getting word that emails have been sent encouraging people to stop people from commenting about it on social networks because MEC’s lawyers are now on the case.

“From: Kieran Allen
Sent: 25 September 2012 08:11
To: MEC London UK All Staff
Subject: Leaving

Hello MEC,

It feels quite strange to be writing my leaving speech after 2 1/2 yrs. of loyal service to the company. It’s the longest I have spent at a company and I owe MEC a lot for my training and development. I leave in a position where I can go and further my career in digital if I so wish and for that I pay MEC great tribute.

However I leave with a horrible taste in my mouth after my working life for the past 8months has been ruined by <redacted>.

Joined MEC in May 2010. Soon after I started to receive continuous praise from Kevin Kirby Account Director and <redacted> for my outstanding performance across accounts (mainly Specsavers) Inc. a commendation from <redacted> to Jason Dormieux about my ability and contribution. I also received high praise from Amy Creasey and Louise Temperley (re general Specsavers performance and securing a PPC turnaround for Colgate inc a 100%+ YoY spend increase).

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