The House of Lies actress showed the video during an appearance on The Ellen DeGeneres Show this week, explaining that fiancé Dax Shepard had arranged for her to meet a sloth as a birthday gift.
Bell - who was seen lying in tears on her bed in the video - told Ellen DeGeneres that she became overwhelmed before the animal was even in the same room as her because it had been a lifelong dream to meet a sloth.
In a Twitter message to fans after the show she said: "You guys are so sweet. it was scary 2 show an ugly cry video but i am so glad if u got a laugh from watching - thats what i was hoping!!! xo (sic)"
Actor Sean Hayes later tweeted: "Still laughing uncontrollably over that video. Can't believe you guys never told us about this," prompting Shepard to respond: "Wait to you see what I'm bringing you on your birthday: a Kodiak Grizzly!!! Surprise! You will cry too!"
Explaining what had happened on Ellen, former Veronica Mars star Bell said. "I'm sitting on my bed knowing that a sloth is here. I start to have a full-fledged panic attack. I don't know how to compete with all this emotion so I just kind of crawl up on the bed and I'm crying so hard.
"Dax knocks on the door with a video camera and says, 'Surprise! I want you to come out... Are you alright?!' He basically sees me foetal on the bed."
House of Lies airs Sundays at 10/9c on Showtime.
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